Necessary (noun) Definition, Meaning & Examples

adjective
  1. essential, indispensable, or requisite: The rotor is a necessary part of the motor.
  2. happening or existing by necessity: The snow has forced a necessary change in our plans.
  3. acting or proceeding from compulsion or necessity; not free; involuntary: a necessary agent.
  4. Logic.
    • (of a proposition) such that a denial of it involves a self-contradiction.
    • (of an inference or argument) such that its conclusion cannot be false if its supporting premises are true.
    • (of a condition) such that it must exist if a given event is to occur or a given thing is to exist.
noun, plural nec·es·sar·ies.
  1. something necessary or required for a particular purpose; necessity.
  2. food, clothing, etc., required by a dependent person and varying with their social or economic position or that of the person upon whom they are dependent.
  3. a privy or toilet.
adjective
  1. needed to achieve a certain desired effect or result; required
  2. resulting from necessity; inevitable
  3. logic
    • (of a statement, formula, etc) true under all interpretations or in all possible circumstances
    • (of a proposition) determined to be true by its meaning, so that its denial would be self-contradictory
    • (of a property) essential, so that without it its subject would not be the entity it is
    • (of an inference) always yielding a true conclusion when its premises are true; valid
    • (of a condition) entailed by the truth of some statement or the obtaining of some state of affairs
  4. (in a nonlogical sense) expressing a law of nature, so that if it is in this sense necessary that all As are B, even although it is not contradictory to conceive of an A which is not B, we are licensed to infer that if something were an A it would have to be B
  5. compelled, as by necessity or law; not free
noun
  1. the money required for a particular purpose
  2. to do something that is necessary in a particular situation
Necessary (noun) Definition, Meaning & Examples

More Definitions