Meaning of the word pertinacious in English

What does pertinacious mean in English? Explore the meaning, pronunciation, and specific usage of this word with Lingoland.

pertinacious

US /ˌpɜːr.tɪˈneɪ.ʃəs/
UK /ˌpɜː.tɪˈneɪ.ʃəs/

Adjective

holding firmly to an opinion or a course of action

Example:
She was pertinacious in her efforts to achieve her goals.
His pertinacious questioning eventually revealed the truth.