Definitions
1.AdjectiveRequired, essential, whether logically inescapable or needed in order to achieve a desired result or avoid some penalty."Although I wished to think that all was false, it was yet necessary that I, who thus thought, must in some sense exist.; It is absolutely necessary that you call and confirm your appointment."
2.AdjectiveUnavoidable, inevitable."If it is absolutely necessary to use public computers, you should plan ahead and forward your e-mail to a temporary, disposable account."
3.AdjectiveDetermined, involuntary: acting from compulsion rather than free will.
4.NounA place to do the "necessary" business of urination and defecation: an outhouse or lavatory.
5.NounNecessity.