C1 adjective tɪˈneɪ.ʃəs
tenacious
粘り強い
Meaning
Not readily letting go of, giving up, or separated from an object that one holds, a position, or a principle; persistent.
Example
Her tenacious spirit helped her overcome hardships.
彼女の粘り強い精神が困難を乗り越える助けとなった。