The crossword solutions for the terms 'WHAT', 'WHO', 'HOW', and 'WHERE' are ELSE, which is a four-letter word. The term 'ELSE' is an adverb that is used to refer to something that is different from what has already been mentioned or is being considered. It can also be used as a pronoun to refer to someone or something that has not been previously mentioned. In addition, it can be used as a conjunction to introduce a clause that contrasts with the preceding clause. Finally, it can be used as an adjective to describe something that is different from what has already been mentioned.