1. (a.) Such as must be; impossible to be otherwise; not to be avoided; inevitable.

2. (a.) Impossible to be otherwise, or to be dispensed with, without preventing the attainment of a desired result; indispensable; requiste; essential.

3. (a.) Acting from necessity or compulsion; involuntary; -- opposed to free; as, whether man is a necessary or a free agent is a question much discussed.

4. (n.) A thing that is necessary or indispensable to some purpose; something that one can not do without; a requisite; an essential; -- used chiefly in the plural; as, the necessaries of life.

5. (n.) A privy; a water-closet.

6. (n.) Such things, in respect to infants, lunatics, and married women, as are requisite for support suitable to station.