radioactivity
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B2 noun ˌreɪ.di.oʊ.ækˈtɪv.ə.ti

radioactivity

Meaning
The emission of ionizing radiation or particles caused by the spontaneous disintegration of atomic nuclei.
Example
Radioactivity is used in medical treatments like cancer therapy.
B2 adjective /ˈrek.ləs/

Reckless

Meaning
acting without thinking about consequences; careless; dangerous;
Example
His reckless driving caused a serious accident.
B2 noun /ˈraɪdər/

rider

Meaning
A person who rides a horse, bicycle, motorcycle, or other vehicle.
Example
The rider fell off the horse.
B2 adjective /rɪˈfaɪnd/

Refined

Meaning
elegant and cultured in appearance, manner, or taste; purified
Example
She has very refined taste in art and music.
B2 adjective /ˈrɪɡ.ər.əs/

rigorous

Meaning
Extremely thorough and demanding in analysis or practice.
Example
A rigorous study plan helps students achieve better results.
B2 adverb /rɪˈpɔːtɪdli/

reportedly

Meaning
according to what is said or believed, although not confirmed
Example
The company has reportedly agreed to the new terms.
B2 noun /ˈreɪ.dɑːr/

Radar

Meaning
a system for detecting the presence, direction, distance of aircraft, ships by sending out radio waves
Example
The radar detected an unknown aircraft approaching the base.
B2 noun, verb /ræmp/

ramp

Meaning
a sloping surface joining two different levels; as a verb, to increase or rise sharply
Example
The car drove up the ramp into the parking garage.
B2 adjective /ˈreɪsɪst/

racist

Meaning
showing or feeling discrimination or prejudice against people of other races
Example
He was accused of making racist comments.
B2 noun /ˈruːlɪŋ/

ruling

Meaning
an official decision made by a judge or authority.
Example
The court’s ruling favored the defendant.
B2 noun /ˈrep.taɪl/

Reptile

Meaning
a cold-blooded animal with scaly skin that lays eggs on land
Example
The lizard is a common reptile found in gardens.
B2 noun /ˈræŋkɪŋ/

ranking

Meaning
a position in a list or hierarchy, especially in terms of performance or importance
Example
His ranking in the competition improved after each round.
B2 verb /ˈrɛnəˌveɪt/

renovate

Meaning
to restore something old to a good state or to improve it
Example
They decided to renovate the old house before moving in.
B2 noun /rɪˈmuː.vəl/

Removal

Meaning
the action of taking something away or eliminating it; dismissal from office
Example
The removal of the old furniture took all day.
B2 noun/adjective /rɪˈpʌblɪkən/

republican

Meaning
a member or supporter of a republican political party or system
Example
The republican candidate won the election.
B2 verb /rɪˈdʒɔɪs/

rejoice

Meaning
to feel or show great joy; to celebrate
Example
The family rejoices at the good news.
B2 noun ˌrev.əˈluː.ʃənz

revolutions

Meaning
Dramatic and wide-reaching changes in political, social, or economic systems, often involving the overthrow of a government or social order.
Example
Revolutions often lead to significant societal changes.
B2 adverb /ˈraɪtli/

Rightly

Meaning
correctly; properly; justly
Example
She rightly pointed out the mistakes in the report.
B2 noun /rɪˈvendʒ/

Revenge

Meaning
the action of inflicting hurt or harm on someone for an injury or wrong suffered at their hands
Example
She sought revenge against those who betrayed her trust.
B2 verb /ˌriː.kənˈsɪd.ər/

reconsider

Meaning
to think about something again, especially to change a decision or opinion
Example
She decided to reconsider her decision about moving abroad.
B2 adjective /rɪˈfreʃ.ɪŋ/

Refreshing

Meaning
making one feel energized and renewed; pleasantly new or different
Example
The cool breeze was refreshing after the hot day.
B2 noun /ˈrerəti/

Rarity

Meaning
the state of being rare; something that is uncommon or scarce
Example
The antique vase was a rarity worth thousands of dollars.
B2 noun /rɪˈvaɪ.vəl/

Revival

Meaning
an improvement in the condition or strength of something; renewed interest in or attention to something
Example
There has been a revival of interest in traditional crafts.
B2 verb /rɪˈkɔːl/

recall

Meaning
to bring (a memory, fact, or situation) back into one's mind
Example
I can't recall the last time we met.
B2 verb /rɪˈtriːv/

retrieve

Meaning
to get something back that was lost or taken; to recover
Example
She managed to retrieve her lost phone from the taxi.
B2 noun /ˈroʊ.lɪŋ pɪn/

Rolling pin

Meaning
a cylindrical tool used for rolling out dough or pastry
Example
Roll the dough flat with a rolling pin.
B2 verb /ˈreɡjəleɪt/

regulate

Meaning
to control or maintain according to rules or laws
Example
The government regulates food safety.
B2 noun, verb /ˈrætəl/

rattle

Meaning
to make a rapid series of short, sharp sounds; a device or object that makes such a sound
Example
The loose window began to rattle in the strong wind.
B2 adjective /ræʃ/

rash

Meaning
Acting quickly without careful consideration; reckless.
Example
It was a rash decision to invest without research.
B2 noun ˈruθləs ˌkɑmpəˈtɪʃən

ruthless competition

Meaning
Fierce and merciless rivalry or contest, without pity or compassion.
Example
Ruthless competition for power leads to societal issues.
B2 noun /ˈruːmər/

rumor

Meaning
a currently circulating story or report of uncertain or doubtful truth.
Example
There’s a rumor that the company will merge next year.
B2 noun /ˌriː.əˈʃʊr.əns/

Reassurance

Meaning
comfort or confidence given to someone to remove their fears or doubts
Example
She needed reassurance that everything would be okay.
B2 noun /ˈruːstər/

rooster

Meaning
A male domestic chicken, especially one that crows.
Example
The rooster crowed at dawn, waking up the whole village.
B2 adjective /ˈrɪdən/

ridden

Meaning
Full of or dominated by something unpleasant.
Example
The country was ridden with corruption.
B2 verb /ˌriːprəˈdjuːs/

reproduce

Meaning
To make a copy of something; to generate offspring.
Example
Many animals reproduce rapidly in favorable conditions.
B2 adjective rɪˈnaʊnd

renowned

Meaning
Known or talked about by many people; famous.
Example
The renowned scientist led the reform panel.
B2 noun /ˈreb.əl/

Rebel

Meaning
a person who resists authority or control
Example
The young rebel refused to follow the school rules.
B2 verb /rɪˈvɜːrt/

revert

Meaning
to return to a previous state, condition, or practice
Example
The system will revert to its original settings after the update.
B2 noun /rɪˈstrɪk.ʃən/

Restriction

Meaning
a limiting condition or measure; the limitation or control of someone or something
Example
There are strict restrictions on smoking in public places.
B2 noun /ˌrep.ɪˈtɪʃ.ən/

Repetition

Meaning
the action of repeating something that has already been said or written
Example
Constant repetition helps students memorize vocabulary effectively.
B2 noun /roʊˈteɪʃən/

Rotation

Meaning
the action of rotating around an axis or center; a single turn
Example
The Earth's rotation takes 24 hours to complete.
B2 verb /ˈruːɪn/

ruin

Meaning
to destroy or damage beyond repair; to spoil completely
Example
Heavy rain could ruin our picnic plans.
B2 noun, verb, adjective /ræŋk/

rank

Meaning
A position in a hierarchy; to place in order according to importance or quality.
Example
She quickly rose to a senior rank in the company.
B2 adverb /rɪˈmɑːrkəbli/

remarkably

Meaning
in a way that is worthy of attention or notice; surprisingly
Example
She did remarkably well in the competition.
B2 noun /rɪˈdʒɛkʃən/

rejection

Meaning
the action of refusing or dismissing something or someone
Example
Her rejection of the offer surprised everyone.
B2 noun /rɪm/

rim

Meaning
the outer edge or border of a circular object
Example
The coffee cup had a chip on its rim.
B2 noun /rɪˈsɛs/

recess

Meaning
A short break from work or school; also a small space set back in a wall.
Example
The children played outside during recess.
B2 noun/verb rɪˈfɔːm

reform

Meaning
Make changes in (something, typically a social, political, or economic institution or practice) in order to improve it.
Example
Reform in the education system was a priority.
B2 noun /raɪˈnɒs.ər.əs/

Rhinoceros

Meaning
a large, heavy animal with thick skin and one or two horns on its nose
Example
The rhinoceros charged through the grassland.
B2 noun /ˌreɡ.jʊˈlær.ɪ.ti/

Regularity

Meaning
the quality of being regular; occurring at fixed intervals or in a consistent pattern
Example
The regularity of his exercise routine helped him stay healthy.
B2 verb /reɪp/

rape

Meaning
to force someone to have sexual intercourse without their consent
Example
The law strictly punishes those who commit rape.
B2 noun rɪˈtɛnʃən

retention

Meaning
The continued possession, use, or control of something
Example
The retention of information is essential for academic success.
B2 verb /rɪˈzɑlv/

resolve

Meaning
to solve a problem; to decide firmly
Example
The manager resolves the conflict between employees.
B2 noun /ræk/

Rack

Meaning
a framework or structure for holding or storing things
Example
She hung her coat on the rack by the door.
B2 noun, verb /rɪˈzɔːrt/

resort

Meaning
A place for rest or recreation; to turn to something for help or solution.
Example
They stayed at a beach resort during their vacation.
B2 noun /ˈraɪfəl/

Rifle

Meaning
a gun with a long barrel that is fired from the shoulder
Example
The soldier carried a rifle during the mission.
B2 noun /reɪk/

Rake

Meaning
a garden tool with a long handle and prongs for gathering leaves; to gather with a rake
Example
He used a rake to gather the fallen autumn leaves.
B2 adjective /ˌrez.ɪˈden.ʃəl/

residential

Meaning
Designed for people to live in.
Example
The institution was fully residential.
B2 adjective ˌriːprəˈdʌktɪv

reproductive

Meaning
Relating to the reproduction of offspring.
Example
The reproductive cycle of pests can cause rapid infestations.
B2 adjective /ˈrest.ləs/

Restless

Meaning
unable to rest or relax; constantly moving or fidgeting
Example
The child was restless during the long car journey.
B2 adjective /rɪˈspek.tɪv/

Respective

Meaning
belonging to each individual; particular to each
Example
The students returned to their respective classrooms after lunch.
B2 verb /ˌriːjuˈnaɪt/

reunite

Meaning
to bring together again after separation
Example
The family was reunited after many years.
B2 noun /ˌref.jʊˈdʒiː/

Refugee

Meaning
a person who has been forced to leave their country in order to escape war, persecution, or natural disaster
Example
The refugee camp provided temporary shelter for thousands of displaced families.
B2 adjective /ˈrɪski/

risky

Meaning
Involving the possibility of danger, harm, or loss
Example
Investing in that startup is risky but could bring high rewards.
B2 adjective /rɪˈmuːvəbəl/

removable

Meaning
able to be removed or taken away
Example
This phone has a removable battery.
B2 noun /ˌren.əˈveɪ.ʃən/

Renovation

Meaning
the act of renovating; restoration to a former better state
Example
The old house underwent a complete renovation last year.
B2 noun ˌrɛvəˈluːʃən

revolution

Meaning
A forcible overthrow of a government or social order, in favor of a new system.
Example
The story is set during the French Revolution.
B2 verb rɪˈstɔːr

restore

Meaning
To bring back to a former or original state; to reinstate.
Example
Restoring the tradition of student politics is necessary.
B2 adverb /ruːˈtiːnli/

routinely

Meaning
as part of a regular procedure; habitually
Example
The staff routinely checks the equipment for safety.
B2 noun /ˈrɪdəl/

Riddle

Meaning
a question or statement intentionally phrased so as to require ingenuity in ascertaining its answer or meaning; a puzzle
Example
The ancient riddle stumped all the scholars for years.
B2 adjective /raɪp/

Ripe

Meaning
fully developed and ready to eat; mature; ready for action or use
Example
The bananas are ripe and ready to eat.
B2 noun /ˌrɛfəˈriː/

referee

Meaning
a person who oversees a game or match to ensure the rules are followed
Example
The referee stopped the game after a foul.
B2 noun /ˌreɡ.jʊˈleɪ.ʃənz/

regulations

Meaning
Rules or directives made and maintained by an authority.
Example
Strict regulations ensure fair practices.
B2 noun /ˈrɔɪəlti/

royalty

Meaning
Members of a royal family or payment made to the owner of a patent, copyright, or natural resource.
Example
The author receives a royalty for every book sold.
B2 verb /ˈrendər/

render

Meaning
to provide or give; to make or cause to become
Example
The artist renders the scene beautifully.
B2 noun /reɪdʒ/

rage

Meaning
intense anger or fury
Example
She shouted in a fit of rage after hearing the news.
B2 noun ˌriːkənˈstrʌkʃn

reconstruction

Meaning
The action or process of reconstructing or being reconstructed.
Example
The reconstruction project took years.
B2 noun /ˈreɪ.zən/

Raisin

Meaning
dried grape
Example
She added raisins to the oatmeal cookies for extra sweetness.
B2 noun /ˈriːzənɪŋ/

reasoning

Meaning
the process of thinking about something in a logical way in order to form a conclusion or judgment
Example
Her reasoning for leaving was clear and logical.
B2 noun ˌrɛstəˈreɪʃən

restoration

Meaning
The process of returning something to its former condition.
Example
The restoration of the forest began after decades of neglect.
B2 noun /rɪˈmeɪn.dər/

Remainder

Meaning
the part that is left over; what remains after the other parts have been taken away
Example
The remainder of the food was stored in the refrigerator.
B2 noun /ˈrɪə.lɪ.zəm/

realism

Meaning
The quality of representing things as they are; a practical or factual view.
Example
Her paintings are admired for their realism.
B2 adjective /rɪˈstrɪk.tɪd/

Restricted

Meaning
limited or controlled; subject to restrictions
Example
Access to this area is restricted to authorized personnel only.
B2 verb /ˈrɛkən/

reckon

Meaning
To think, believe, or expect something; to calculate or estimate.
Example
I reckon it will rain later today.
B2 noun /ˌrezəˈveɪʃən/

Reservation

Meaning
the action of reserving something; an arrangement whereby something is reserved for a particular person; a qualification to an expression of agreement or approval
Example
I made a reservation at the restaurant for tonight.
B2 noun ˌreɪdɪˈeɪʃən

radiation

Meaning
The emission of energy as electromagnetic waves or as moving subatomic particles.
Example
Radiation from the sun can be harmful without protection.
B2 adverb /rɪˈlʌk.tənt.li/

Reluctantly

Meaning
in an unwilling manner; with hesitation or resistance
Example
She reluctantly agreed to help with the project.
B2 noun /ˈreɪtɪŋ/

rating

Meaning
an evaluation or assessment, usually numerical
Example
The movie received a high rating from critics.
B2 adjective /rɪˈzɪl.i.ənt/

resilient

Meaning
Able to withstand or recover quickly from difficult conditions.
Example
Resilient materials ensure durability.
B2 noun /rʌst/

Rust

Meaning
reddish-brown coating formed on iron or steel by oxidation; corrosion
Example
The old car was covered in rust after years of neglect.
B2 adjective /ˈruːθ.ləs/

Ruthless

Meaning
showing no pity or compassion; cruel; merciless
Example
The ruthless dictator showed no mercy to his enemies.
B2 adjective /ˈrɒt.ən/

Rotten

Meaning
decayed; spoiled; bad
Example
The apple is rotten and should be thrown away.
B2 noun rɪˈzentmənt

resentment

Meaning
Bitter indignation at having been treated unfairly.
Example
Resentment grew among the students.
B2 noun /rɪˈstreɪnt/

Restraint

Meaning
the action of keeping someone or something under control; self-control
Example
She showed great restraint in not responding to the criticism.
B2 noun /ˈraɪvəlri/

Rivalry

Meaning
competition for the same objective or for superiority in the same field; the state of being rivals
Example
The rivalry between the two teams made the match exciting.
B2 noun /ˈrɪb.ən/

ribbon

Meaning
a long, narrow strip of fabric used for tying or decoration
Example
She tied her hair with a red ribbon.
B2 adjective ˌrev.əˈluː.ʃən.ər.i

revolutionary

Meaning
Involving or causing a complete or dramatic change.
Example
Revolutionary ideas are reshaping the industry.
B2 adjective rəʊˈbʌst

robust

Meaning
Strong and healthy; vigorous; able to withstand or overcome adverse conditions.
Example
The robust infrastructure ensures reliable communication.
B2 verb /reɪn/

reign

Meaning
to rule as a king or queen; to be dominant
Example
The queen reigned for over sixty years.
B2 noun /ˈreɪʃoʊ/

ratio

Meaning
a relationship between two numbers showing how many times the first number contains the second
Example
The ratio of boys to girls in the class is 2:1.
B2 adjective /ˈreɪʃəl/

racial

Meaning
relating to a race of people
Example
Racial equality is an important issue in many societies.
B2 noun /rɪˈmaɪndər/

reminder

Meaning
something that helps you remember a fact, event, or action that you need to do or recall
Example
He set a reminder to call his mother on her birthday.
B2 noun /ˈrest.ləs.nəs/

Restlessness

Meaning
the inability to rest or relax as a result of anxiety or boredom
Example
His restlessness during the long meeting was obvious to everyone.
B2 noun ˈrɛvənuː

revenue

Meaning
Income, especially when of a company or organization.
Example
The company's revenue grew by 10% this year.
B2 verb /rɪˈteɪn/

retain

Meaning
to keep possession of something
Example
The company decided to retain its experienced employees.
B2 adverb /ˈræp.ɪd.li/

Rapidly

Meaning
at a fast speed; quickly
Example
The company is rapidly expanding into new markets.
B2 verb rɪˈzaɪn

resign

Meaning
Voluntarily leave a job or other position.
Example
Ministers were forced to resign.
B2 adjective /rɪˈsɔːrsfəl/

resourceful

Meaning
Having the ability to find quick and clever ways to overcome difficulties.
Example
She is very resourceful when it comes to solving unexpected problems.
B2 noun /rɪˈfreʃ.mənt/

Refreshment

Meaning
food and drink that is served as a light meal; something that refreshes
Example
We served light refreshments after the meeting.
B2 noun rɪˈpʌb.lɪk

republic

Meaning
A state in which supreme power is held by the people and their elected representatives, with an elected or nominated president rather than a monarch.
Example
A republic is governed by representatives of the people.
B2 verb /rɪˈstreɪn/

restrain

Meaning
to hold back or control; to limit or restrict
Example
Please restrain your dog.
B2 verb /rɪˈliːv/

relieve

Meaning
to make pain, distress, or difficulty less severe or serious
Example
The medicine helped relieve his headache.
B2 noun ˌrɛzɪɡˈneɪʃən

resignation

Meaning
The acceptance of something undesirable but inevitable; giving up.
Example
Her resignation from the position was unexpected.
B2 noun /ˈrɪk.ʃɔː/

Rickshaw

Meaning
a light two-wheeled passenger vehicle drawn by one or more people
Example
We took a rickshaw to reach the busy marketplace.
B2 verb /ˌriːəˈreɪndʒ/

rearrange

Meaning
to change the order or position of something
Example
She decided to rearrange the furniture in her living room.
B2 adjective /rɪˈlaɪ.ənt/

reliant

Meaning
depending on someone or something for support
Example
The country is too reliant on imported goods.
B2 noun, verb /ˈriːteɪl/

retail

Meaning
the sale of goods to the public in small quantities for use or consumption rather than for resale
Example
The company specializes in the retail of clothing and accessories.
B2 noun /ˈrɒbər/

robber

Meaning
a person who steals property from others, often using force or threat
Example
The robber was caught after a quick police chase.
B2 verb /rɪˈstrɪkt/

restrict

Meaning
To limit the size, amount, or range of something.
Example
The government decided to restrict the use of plastic bags.
B2 verb /rɪˈzɛnt/

resent

Meaning
to feel bitterness or displeasure about something or someone
Example
She began to resent the constant criticism from her boss.
B2 verb /reɪd/

raid

Meaning
to attack suddenly; to search and seize
Example
Police raid the illegal gambling house.