Definition of: necessity

(nə·ses′ə·tē) noun plural ·ties
1. The quality of being necessary: Food is a necessity for growth.
2. That which is unavoidable or necessary, as in physical, moral, or logical sequence; a state of things rendering something inevitable.
3. That which is indispensably requisite to an end desired: often in the plural: the necessities of life; also, the fact of being indispensable; indispensableness.
4. The condition of being in want; poverty.
5. The doctrine that all events are necessarily determined. It embraces physical determinism, or fatalism, and philosophical or rational determinism, thus precluding chance or free will.
—of necessity Necessarily; unavoidably. [<L necessitas, -tatis] Synonyms: compulsion, destiny, emergency, essential, exigency, extremity, fatality, fate, indispensability, indispensableness, need, requirement, requisite, unavoidableness, urgency, want. An essential is something, as a quality or element, that belongs to the essence of something else so as to be inseparable from it in its normal condition, or in any complete idea or statement of it. Need and want always imply a lack; but necessity simply denotes the exclusion of any alternative either in thought or fact. See PREDESTINATION, WANT. Compare NECESSARY. Antonyms: choice, contingency, doubt, doubtfulness, dubiousness, fortuity, freedom, option, possibility, uncertainty.