C1 adjective tɪˈneɪ.ʃəs
tenacious
hartnäckig
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.
Ihr hartnäckiger Geist half ihr, Schwierigkeiten zu überwinden.