nessary

Adjective

necessary (comparative necessarier or more necessary, superlative necessariest or most necessary)

1. Required, 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.

   Synonyms:

   basic, essential, indispensable, necessar, necessitous, needed, prerequisite, required, requisite

   Antonyms:

   unnecessary

2. Unavoidable, inevitable.
   • If it is absolutely necessary to use public computers, you should plan ahead and forward your e-mail to a temporary, disposable account.

   Synonyms:

   inevitable, natural

   Antonyms:

   evitable, incidental, impossible

3. (obsolete) Determined, involuntary: acting from compulsion rather than free will.
   • But that a necessary being should give birth to a being with any amount, however limited, of moral freedom, is infinitely less conceivable than that parents of the insect or fish type should give birth to a perfect mammal.1871, Richard Holt Hutton, Essays, volume I, page 53

See all 6 meanings of necessary