Definition of prime
1a often capitalized : the second of the canonical hoursb : the first hour of the day usually considered either as 6 a.m. or the hour of sunrise
3 : the most active, thriving, or satisfying stage or period <in the prime of his life>
4 : the chief or best individual or part : pick <prime of the flock, and choicest of the stall — Alexander Pope>
5 : prime number
6a : the first note or tone of a musical scale : tonicb : the interval between two notes on the same staff degree
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 : prime rate
Examples of prime in a sentence
young college graduates in the prime of life
The interest rate is two percent plus prime.
Origin and Etymology of prime
Middle English, from Old English prīm, from Latin prima hora first hour
First Known Use: before 12th century
Other Calendar Terms
prime
Definition of prime
1 : first in time : original
2a : of, relating to, or being a prime number — compare relatively primeb : 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>
3a : 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 : not deriving from something else : primary
primely
adverbprimeness
nounExamples of prime in a sentence
The wine industry is of prime importance to the California economy.
The police have not yet named the prime suspect in the murder investigation.
The house is expensive because it's in a prime location.
Origin and Etymology of prime
Middle English, from AngloFrench, feminine of prim first, from Latin primus; akin to Latin prior
First Known Use: 15th century
Other Business Terms
prime
Definition of prime
primed
;priming
transitive verb
2a : to prepare for firing by supplying with primingb : to insert a primer into (a cartridge case)
3 : to apply the first color, coating, or preparation to <prime a wall>
4a : 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>
5 : to instruct beforehand : coach <primed the witness>
6 : stimulate
intransitive verb
: to become prime
prime the pump
: to take steps to encourage the growth or functioning of something
Examples of prime in a sentence
She was obviously primed for the questions at the press conference.
Both teams are primed for battle and ready to play.
We sanded and primed the woodwork before painting.
Origin and Etymology of prime
probably from ^{1}prime
First Known Use: 1513
PRIME Defined for English Language Learners
Definition of prime for English Language Learners

: the period in life when a person is best in health, strength, etc. : the most active or successful time of a person's life
prime
Definition of prime for English Language Learners

: 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
prime
Definition of prime for English Language Learners

: 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
PRIME Defined for Kids
Definition of prime for Students
: the period in life when a person is best in health, looks, or strength
Definition of prime for Students
: first in importance, rank, or quality <Spring is a prime season to work outdoors.>
Definition of prime for Students
primed
priming
1 : to put a first color or coating on <Prime the wall before painting.>
2 : to put into working order by filling <prime a pump>
3 : to make (someone or something) ready <The coach is priming him to be quarterback.>
Law Dictionary
prime
Legal Definition of prime
primed
priming
: to have priority over <a perfected security interest primes an unperfected one>
Learn More about prime

See words that rhyme with prime Thesaurus: All synonyms and antonyms for prime Spanish Central: Translation of prime Nglish: Translation of prime for Spanish speakers Britannica English: Translation of prime for Arabic speakers Britannica.com: Encyclopedia article about prime
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