(one's) level best

(one's) level best

The very best one is able to do at some task or activity. I'm just not good at math, so, believe me, a B- in Algebra means that I've done my level best. I know you're worried about the game today, but just go out there and give it your level best.
See also: level
Farlex Dictionary of Idioms.

someone's level best

one's very best effort. I will do my level best to find your husband. Don't go to a whole lot of trouble. Your level best is good enough.
See also: level
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

level best

see under do one's best.
See also: level
The American Heritage® Dictionary of Idioms by Christine Ammer.

level best

n. one’s very best effort. I will do my level best to find your husband.
See also: level
McGraw-Hill's Dictionary of American Slang and Colloquial Expressions

(one's) level best

The best one can do in an earnest attempt: I did my level best in math class.
See also: level
American Heritage® Dictionary of the English Language, Fifth Edition.
See also:
  • level best
  • try (one's) level best
  • (had) best (do something)
  • best do
  • as best (one) can
  • as best one can
  • as best you can
  • bring out the best in
  • bring out the best in (one)
  • bring out the best in somebody