Take a whack is an idiom that means to make an attempt at something, usually with enthusiasm. It can also mean to take a swing at something, such as a ball or a person. The crossword solutions for this term are 'TRY', which is a verb meaning to make an effort or attempt to do something. This phrase is often used in the context of trying something new or challenging, and it implies that one should not be afraid to give it a go.