prime

1 of 3

adjective

ˈprīm 

1

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

2

: first in time : original

3

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 (such as prime numbers and prime polynomials)

a prime factorization

4

: not deriving from something else : primary

primely adverb

primeness noun

prime

2 of 3

noun

1

: the most active, thriving, or satisfying stage or period

in the prime of his life

2

: the chief or best individual or part : pick

prime of the flock, and choicest of the stall

—Alexander Pope

3

a

: the earliest stage

b

: spring

c

: youth

4

: prime rate

5

: prime number

6

a

: the first note or tone of a musical scale : tonic

b

: the interval between two notes on the same staff degree

7

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

8

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

prime

3 of 3

verb

primed; priming

transitive verb

1

: fill, load

2

a

: to prepare for firing by supplying with priming

b

: to insert a primer into (a cartridge case)

3

: to apply the first color, coating, or preparation to

prime a wall

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 (such 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

Phrases

prime the pump

: to take steps to encourage the growth or functioning of something

Synonyms

Adjective

• chief
• presiding
• foremost
• supreme
• commanding
• top
• primary
• leading
• first
• principal
• lead
• senior
• high

Noun

• bloom
• blooming
• heyday
• flower

Examples of prime in a Sentence

Adjective

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.

Noun

young college graduates in the prime of life

The interest rate is two percent plus prime.

Verb

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.

Recent Examples on the Web

Adjective

Six of those completions went to Mahomes' longtime teammate Travis Kelce, who finished the prime-time victory with a team-high 99 yards and one touchdown. —Matt Audilet, MSNBC Newsweek, 28 Oct. 2025

Hollywood studios welcome Netflix’s acknowledgment of theatrical as long as the streamer doesn’t step on their toes — whether by hogging the coveted premium large formats or scheduling its programming on prime release dates. —Rebecca Rubin, Variety, 27 Oct. 2025

Noun

Located on the top floor of a historic 1920s building right by Fulton Market, this prime Airbnb is great for entertaining. —Gabriela Ulloa, Architectural Digest, 25 Oct. 2025

Search online for local organizations that use past-their-prime pumpkins. —Patricia Shannon, Southern Living, 24 Oct. 2025

Verb

But after withering on the Houston bench for two years in an overcrowded forward rotation, he’s primed for a leap in Year 3. —John Hollinger, New York Times, 25 Oct. 2025

The brain, already primed by expectation or anxiety, magnifies those sensations, producing very real pain, bloating, brain fog, fatigue or mood swings. —New Atlas, 24 Oct. 2025

Word History

Etymology

Adjective

Middle English, "first, original, in an initial stage," borrowed from Anglo-French, originally feminine of prim "first, earliest, original, main, most important," going back to Latin prīmus "first" (ordinal corresponding to ūnus "one, foremost, earliest, of first importance, of the highest quality,") going back to earlier *prīsmos, syncopated from *prīsomos, from dialectal Indo-European *pri "in front, before" + *-is-m̥mo-, superlative suffix (from *-is-, comparative suffix + *-m̥mo-, superlative suffix) — more at prior entry 2

Note: The combined comparative-superlative suffix *-is-m̥mo- as a productive superlative suffix is peculiar to Italic and Celtic. The assumption that *-is-m̥mo- yields *-isomo- in Latin (rather than *-em- or *-am-) is based on Michael Weiss, Outline of the Historical and Comparative Grammar of Latin (Beech Stave Press, 2011), p. 105. (Weiss suggests as a prime example homō "man, human," from *ǵhm̥mō.)

Noun

Middle English, going back to Old English prīm, borrowed from Medieval Latin prīma (short for Latin prīma hōra "first hour"), from feminine of Latin prīmus "first, earliest"; in senses other than sense 8 borrowed in part from Latin prīmum "first part, beginning stages" (in plural prīma) or prīmus "notable person, leading citizen," noun derivatives of prīmus, adjective — more at prime entry 1

Verb

of uncertain origin

Note: Possibly a derivative of prime entry 1, if priming something was taken to mean performing an essential preliminary stage. However, if early uses meaning simply "to load, fill" (earliest in Scots, in Gavin Douglas's translation of the Aeneid, 1513) are the original senses, the painting and weapons senses may be by secondary association with prime entry 1 and its etymons. Supporting the hypothesis of an original meaning "load" would be the apparent derivative primage "money paid by a shipper to a captain for care of the cargo," attested as English in 1476, and as Latin primagium as early as 1297. Compare in the same sense prime-gilt (earliest in Scots, 1576), alongside Middle High German primegelt, primgelt (1468) and Middle Dutch priemgelt (1460), with gelt "money." However, none of these words lead any closer to the origin of the English verb.

First Known Use

Adjective

15th century, in the meaning defined at sense 2

Noun

before the 12th century, in the meaning defined at sense 8a

Verb

1513, in the meaning defined at transitive sense 1

Phrases Containing prime

• double prime
• in one's prime
• past one's prime
• prime cost
• prime meridian
• prime minister
• prime mover
• prime number
• prime rate
• prime target
• prime the pump
• prime time
• relatively prime
• the prime meridian

Rhymes for prime

• chime
• chyme
• climb
• clime
• crime
• dime
• grime
• lime
• lyme
• mime
• rhyme
• slime

Kids Definition

prime

1 of 3 noun

ˈprīm 

1

: the first part : the earliest stage

2

: the most vigorous, prosperous, or satisfying stage or period

in the prime of one's life

3

: the best individual or part

4

: prime number

5

: the symbol ′

prime

2 of 3 adjective

1

: first in time : original

2

a

: of, relating to, or being a prime number

b

: expressed as a product of prime factors

the prime factorization of 12 is 2 · 2 · 3

3

a

: first in rank or importance

our prime responsibility

b

: being highest in quality or value

prime farmland

c

: of the highest grade of meat

prime beef

prime

3 of 3 verb

primed; priming

1

: to get ready for firing by putting in priming

prime a rifle

2

: to put a first color or coating on (an unpainted surface)

3

: to put into working order by filling

prime a pump

4

: to make (someone) ready to do something

teams primed to win

Etymology

Noun

Old English prīm "a religious service for the first hour of the day," from Latin prima (hora) "first (hour)," from primus "first" — related to premier, prima donna, primeval, prince

Legal Definition

prime

1 of 2 noun

1

: prime rate

2

: general contractor

prime

2 of 2 transitive verb

primed; priming

: to have priority over

a perfected security interest primes an unperfected one