The crossword solution for the term 'APT RHYME FOR 'CRUDE' AND 'RUDE'' is 'LEWD, ' which is a four-letter word. The term 'LEWD' is an adjective that means 'indecent or obscene in a way that is considered humorous.' It is often used to describe behavior that is considered socially unacceptable, such as sexual innuendo or jokes. In this case, it is being used as an apt rhyme for the words 'CRUDE' and 'RUDE, ' which are both words that can be used to describe someone who is behaving in an inappropriate manner.