best

(noun): The supreme effort one can make, or has made.
(noun): One's best behavior.
(noun): The person (or persons; or thing or things) that is (are) most excellent.
(verb): To surpass in skill or achievement.
(verb): To beat in a contest
(adjective): Most; largest.
(adjective): Most superior; most favorable.
(adjective): (of people)
(adjective): (of capabilities)
(adjective): (properties and qualities)
(adjective): (when with and) Very, extremely. See good and.
(adjective): Holy (especially when capitalized) .
(adjective): (of quantities)
(adverb): (manner) Accurately, competently, satisfactorily.
(adverb): (manner) Completely, fully.
(adverb): (degree) To a significant degree.
(adverb): (degree) Very (as a general-purpose intensifier).
(adverb): In a desirable manner; so as one could wish; satisfactorily; favourably; advantageously.

I did my best.
I was somewhat distant lately, and my lady promised me head every Tuesday of the week when I'm nice to her, so I better be on my best.
Unpacking took the best part of a week.
In my opinion, mushrooms are the best pizza toppings.
The soup is good and hot.