Necessarily is an adverb that means something that must be done or is unavoidable. It can be broken down into three words: INEVITABLY (10 letters), Perforce (8 letters) and NEEDS (5 letters). INEVITABLY means that something is certain to happen, Perforce means that something is done out of necessity, and NEEDS means that something is required. All three words are related to the term Necessarily, as they all imply that something must be done or is unavoidable.