noun pl. necessities -·ties

1. the power of natural law that cannot be other than it is; natural causation; physical compulsion placed on man by nature; fate
2. anything that is inevitable, unavoidable, etc. as a result of natural law; that which is necessary in natural sequence
3. 1. the compulsion or constraint of man-made circumstances, habit, custom, law, etc.; logical or moral conditions making certain actions inevitable or obligatory faced by the necessity to earn a living
   2. what is required by this social or legal compulsion
4. great or imperative need
5. something that cannot be done without; necessary thing: often used in pl.
6. the state or quality of being necessary
7. want; poverty

Etymology: ME necessite < OFr nécessité < L necessitas < necesse: see necessary