necessary

/'nesisəri/
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necessary

A balanced diet is necessary for good health.

Definition
  1. Adjective:

    • Required to be done, achieved, or present; needed; essential: Something that is "necessary" must happen or exist because it is required by circumstances, logic, or natural law.
    • Inevitably resulting from or logically following from conditions: A "necessary" outcome or conclusion is one that is certain and unavoidable given the preceding facts or premises.
  2. Noun:

    • A thing that is needed or essential: "Necessaries" (often used in plural) are items or conditions required for a particular purpose or for basic living.
    • (The necessary) Informal: A term for money needed for a purpose, or (dated British informal) a toilet.
Usage Examples
  • Adjective:

    • A passport is necessary for international travel.
    • It is necessary to drink water to survive.
    • Given the evidence, a guilty verdict was a necessary conclusion.
  • Noun:

    • The government provided food and other necessaries to the refugees.
    • I've packed all the necessaries for the camping trip.
    • (Informal) He went to the bank to get the necessary for the car payment.
Advanced Usage
  • Philosophical/Logical Necessity: In logic and philosophy, a "necessary" condition is one without which something cannot occur or be true. Its counterpart is a "sufficient" condition.

    • Oxygen is a necessary condition for combustion, but it is not sufficient on its own (you also need fuel and heat).
  • Necessary Evil: A common idiom describing something undesirable that must be accepted or endured to achieve a beneficial result.

    • Paying taxes is often seen as a necessary evil.
Variants and Related Words
  • Necessitate (verb): To make something necessary as a result or requirement.
    • The storm necessitated a change of plans.
  • Necessity (noun): The state or fact of being required or unavoidable; an indispensable thing.
    • Water is a basic necessity of life.
  • Necessarily (adverb): As a necessary result; inevitably.
    • Expensive food is not necessarily better.
Synonyms
  • Adjective: Essential, required, needed, indispensable, vital, mandatory, obligatory, inevitable, unavoidable.
  • Noun: Requirement, essential, requisite, prerequisite, need.
Antonyms
  • Adjective: Unnecessary, superfluous, optional, dispensable, nonessential, avoidable.
  • Noun: Luxury, extra, nonessential.
Related Phrases and Idioms
  • If necessary: Used to indicate what will be done if it becomes required.
    • We can postpone the meeting if necessary.
  • A necessary part of: An essential component.
    • Trust is a necessary part of any strong relationship.
  • Do the necessary: (Informal) To do what is required in a situation.
    • I'll do the necessary to get the project back on track.
necessary

A balanced diet is necessary for good health.

Adjective
  1. unavoidably determined by prior circumstances
    • the necessary consequences of one's actions
  2. absolutely essential
Noun
  1. anything indispensable
    • food and shelter are necessities of life
    • the essentials of the good life
    • allow farmers to buy their requirements under favorable conditions
    • a place where the requisites of water fuel and fodder can be obtained