Read the dictionary definition of best. All definitions for this word.
1. the supreme effort one can make
1. they did their best
2. the person who is most outstanding or excellent; someone who tops all others
1. he could beat the best of them
3. Canadian physiologist (born in the United States) who assisted F. G. Banting in research leading to the discovery of insulin (1899-1978)
4. get the better of
1. the goal was to best the competition
5. (comparative and superlative of `well') wiser or more advantageous and hence advisable
1. it would be better to speak to him
2. the White House thought it best not to respond
6. (superlative of `good') having the most positive qualities
1. the best film of the year
2. the best solution
3. the best time for planting
4. wore his best suit
7. it would be sensible
1. you'd best stay at home
8. in a most excellent way or manner
1. he played best after a couple of martinis
9. from a position of superiority or authority
1. father knows best
2. I know better.
See also:
Merriam-Webster definition of best