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noun \ˈprīm\

Simple Definition of prime

  • : the period in life when a person is best in health, strength, etc. : the most active or successful time of a person's life

Full Definition of prime

  1. 1 a often capitalized :  the second of the canonical hours b :  the first hour of the day usually considered either as 6 a.m. or the hour of sunrise

  2. 2 a :  the earliest stage b :  spring c :  youth

  3. 3 :  the most active, thriving, or satisfying stage or period <in the prime of his life>

  4. 4 :  the chief or best individual or part :  pick <prime of the flock, and choicest of the stall — Alexander Pope>

  5. 5 :  prime number

  6. 6 a :  the first note or tone of a musical scale :  tonic b :  the interval between two notes on the same staff degree

  7. 7 :  the symbol ′ used to distinguish arbitrary characters (as a and a′), to indicate a specific unit (as feet or minutes of time or angular measure), or to indicate the derivative of a function (as p′ or f′(x)) — compare double prime

  8. 8 :  prime rate

Examples of prime

  1. young college graduates in the prime of life

  2. The interest rate is two percent plus prime.

Origin of prime

Middle English, from Old English prīm, from Latin prima hora first hour

First Known Use: before 12th century

Other Calendar Terms

Rhymes with prime




Simple Definition of prime

  • : most important

  • : of the highest quality or value

  • —used to say that someone or something is a very good example of a particular kind of person or thing

Full Definition of prime

  1. 1 :  first in time :  original

  2. 2 a :  of, relating to, or being a prime number — compare relatively prime b :  having no polynomial factors other than itself and no monomial factors other than 1 <a prime polynomial> c :  expressed as a product of prime factors (as prime numbers and prime polynomials) <a prime factorization>

  3. 3 a :  first in rank, authority, or significance :  principal <a prime example> b :  having the highest quality or value <prime farmland> c :  of the highest grade regularly marketed —used of meat and especially beef

  4. 4 :  not deriving from something else :  primary

prime·ly adverb
prime·ness noun

Examples of prime

  1. The wine industry is of prime importance to the California economy.

  2. The police have not yet named the prime suspect in the murder investigation.

  3. The house is expensive because it's in a prime location.

Origin of prime

Middle English, from Anglo-French, feminine of prim first, from Latin primus; akin to Latin prior

First Known Use: 14th century




Simple Definition of prime

  • : to make (someone) ready to do something

  • : to make (something) ready for use

  • : to cover (a surface) with special paint in order to prepare it for the final layer of paint

Full Definition of prime


  1. transitive verb
  2. 1 :  fill, load

  3. 2 a :  to prepare for firing by supplying with priming b :  to insert a primer into (a cartridge case)

  4. 3 :  to apply the first color, coating, or preparation to <prime a wall>

  5. 4 a :  to put into working order by filling or charging with something <prime a pump with water> b :  to supply with an essential prerequisite (as a hormone, nucleic acid, or antigen) for chemical or biological activity <primed female mice with estrogen>

  6. 5 :  to instruct beforehand :  coach <primed the witness>

  7. 6 :  stimulate

  8. intransitive verb
  9. :  to become prime

prime the pump
  1. :  to take steps to encourage the growth or functioning of something

Examples of prime

  1. She was obviously primed for the questions at the press conference.

  2. Both teams are primed for battle and ready to play.

  3. We sanded and primed the woodwork before painting.

Origin of prime

probably from 1prime

First Known Use: 1513

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February 6, 2016

an official order, decree, or edict

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