do one's best

do one's best (third-person singular simple present does one's best, present participle doing one's best, simple past did one's best, past participle done one's best)

1. To do as best one can.

   Synonyms: try one's best, do one's utmost, give it one's best shot

• do one's worst

• “do one's best”, in Lexico, Dictionary.com; Oxford University Press, 2019–present.
• “do one's best”, in Merriam–Webster Online Dictionary.
• “do your best” in Longman Dictionary of Contemporary English, Longman.
• “do try your best” (US) / “do try your best” (UK) in Macmillan English Dictionary.