\ ˈprīm \

Definition of prime

 (Entry 1 of 3)

1a 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
2a : the earliest stage
b : spring
c : youth
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
6a : 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



Definition of prime (Entry 2 of 3)

1 : first in time : original
2a : 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
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


primed; priming

Definition of prime (Entry 3 of 3)

transitive verb

1 : fill, load
2a : 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
4a : 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
prime the pump
: to take steps to encourage the growth or functioning of something

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Other Words from prime


primely adverb
primeness noun

Examples of prime in a Sentence


young college graduates in the prime of life The interest rate is two percent plus prime.


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.


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.
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Recent Examples on the Web: Noun

Elliott, who rushed for 983 yards and seven touchdowns despite missing six games because of a suspension in his second season, is about to hit the prime of his career, Tomlinson said. Stefan Stevenson, star-telegram, "Ezekiel Elliott has some work to do, this Hall of Famer says. "I think he understands what he means to the Dallas Cowboys." | Fort Worth Star-Telegram," 19 May 2018 The efficiency of the Venetian stroke allows gondoliers to continue rowing beyond their athletic prime. Jillian Berman, WSJ, "A Model Gondolier With a Relentless Regimen," 20 Oct. 2018 Well past his prime at age 35, O’Neal was an odd fit for D’Antoni’s free-flowing system. Connor Letourneau, San Francisco Chronicle, "Steve Kerr, Mike D’Antoni: Hoops savants who clashed in the past," 11 May 2018 Even Fujifilm’s sometimes-sluggish f/1.4 primes have gotten a shot in the arm and seem to lock focus faster on the X-T3. Chris Welch, The Verge, "Fujifilm X-T3 review: the do-everything camera," 24 Oct. 2018 Corn relish makes for a prime topping, and this is the time of year to do it. Becky Krystal, The Seattle Times, "Quick and easy garnishes to glam up your plain, boring food," 4 Sep. 2018 What better way to start a new school year and prime yourself to be creative and productive than to do a space refresh? Madeline O'malley, Teen Vogue, "Back to School Awards 2018: Best Dorm Decor," 1 Aug. 2018 The Turkish prime ministry issued a temporary media ban Sunday night on reporting the aftermath of the accident, citing national security and public order. Washington Post, "Turkey: Train derailment kills at least 10, injures 73," 8 July 2018 Giving him a full max over five seasons could cripple the back-half of James Harden’s prime. Rohan Nadkarni,, "Buyer Beware: Five Pricey Free Agents to Avoid," 27 June 2018

Recent Examples on the Web: Adjective

The hotel's prime lakeside perch also means stunning views from your balcony. Leena Kim, Town & Country, "What to Do in St. Moritz During January," 7 Jan. 2019 While the 2018 lunar eclipse won’t be visible from the U.S., places all around the world — including the Middle East and Greece — will be in prime locations to see the celestial event. Gabby Raymond, Time, "These Are the Best Places to See the Lunar Eclipse on July 27," 10 July 2018 Literally, zero need to get to the pool early and secure your prime lounge chair position. Sienna Fantozzi, House Beautiful, "This Might Be The Best Hotel Pool We've Ever Seen," 1 Oct. 2018 Instagram narcissism leads to blows: 44-yo American woman and Dutch teenager start an 8-person brawl at Rome’s Trevi Fountain over prime selfie positions. Janine Puhak, Fox News, "8 tourists brawl at Rome’s Trevi Fountain over selfie spot," 10 Aug. 2018 Tobin Hill is in a prime position due to its geographic location, easy access to the highway and the medical center... Richard Webner, San Antonio Express-News, "Condo towers would bring taste of New York to Tobin Hill," 13 July 2018 But now the Mavericks are in prime position to sign Jordan with $27 million of salary cap space. Roger Pinckney, star-telegram, "DeAndre Jordan opts out of deal with Clippers. Will he really come to Dallas this time?," 29 June 2018 When eel prices spiked, Sheldon was in a prime position to cash in. National Geographic, "19 Eel Smugglers Sentenced, But Lucrative Trade Persists," 27 June 2018 All four teams had a chance to advance in games that were being played simultaneously and Sweden's comprehensive lead over Mexico put Germany into prime position to advance as well — provided the Germans could score against the South Koreans. Houston Chronicle, "Mexico, Sweden advance from group stage; defending World Cup champ Germany eliminated," 27 June 2018

Recent Examples on the Web: Verb

Who Hofmann decides to prime the network with could set the tone. Julia Alexander, The Verge, "Byte’s creator culture will make or break Vine 2," 18 Dec. 2018 The previous speed record-holder—at least for ants—is the trap-jaw ant, which uses a combination of highly specialized muscles to prime its jaw before using a different set to snap it shut at speeds around 50 miles per hour. Avery Thompson, Popular Mechanics, "The Dracula Ant's Lightning Mandibles Make It the Fastest Animal in the World," 12 Dec. 2018 Did the Tamagotchi prime us to become slaves to meaningless beeping? Sarah Jeong, The Verge, "My Tamagotchi is everything that went wrong with our future," 17 June 2018 And over the last few years developer Square Enix has been attempting to prime the global market to make DQXI a hit. Andrew Webster, The Verge, "Dragon Quest XI could be the one," 26 June 2018 Too bad Sum of All Fears did so little to prime the public for such debates. Joe Pappalardo, Popular Mechanics, "Hollywood Has No Idea How Nukes Work," 2 Apr. 2018 And try to prime attendees for any special expectations right from the outset. Priya Parker, WSJ, "We’ve Got to Stop Meeting Like This: Tips for Better Workplace Gatherings," 4 May 2018 In fact, Camp is giving away free money to prime the pump. Robert Hackett, Fortune, "Uber Creator Invents New Cryptocurrency—And Wants Your Help Making It Reality," 1 Mar. 2018 This will prevent one process from being able to prime the branch predictor used by another, which should curtail, if not outright eliminate, the Spectre branch prediction attack. Peter Bright, Ars Technica, "Meltdown and Spectre: Here’s what Intel, Apple, Microsoft, others are doing about it," 5 Jan. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'prime.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of prime


before the 12th century, in the meaning defined at sense 1a


15th century, in the meaning defined at sense 1


1513, in the meaning defined at transitive sense 1

History and Etymology for prime


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


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


probably from prime entry 1

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Statistics for prime

Last Updated

14 Jan 2019

Look-up Popularity

Time Traveler for prime

The first known use of prime was before the 12th century

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More Definitions for prime



Financial Definition of prime

What It Is

In the finance world, prime is short for prime rate, which is the interest rate commercial banks charge their most creditworthy customers, which are usually corporations.

How It Works

Anyone who has borrowed money knows that different banks charge different interest rates. So when people refer to the prime rate, they are usually referring to the average prime rate among banks. The Wall Street Journal is the most common source for this statistic. It calculates the average prime rate by surveying the 30 largest banks in the U.S. Below is a sample graph of the historical average prime rate published by the Federal Reserve, which surveys 25 banks across the nation.

In general, the rate is the same among nearly all the surveyed banks, and they tend to change their rates at the same time. When 75% of these banks (23 banks) change their rates, The Wall Street Journal changes its average.

Why It Matters

Prime is one of the most widely used market indicators, albeit a lagging one, and it is a major benchmark for mortgage and credit card rates. It is often the basis for adjustable-rate loans. For example, if a bank is offering a home equity loan at “prime plus 5” and its prime rate is 6%, then the bank is essentially offering borrowers an 11% loan (6% + 5%) whose interest rate will fluctuate with the prime rate. It is important to remember that not everyone qualifies for prime -- this rate is only for customers least likely to default.

Source: Investing Answers



English Language Learners Definition of prime

 (Entry 1 of 3)

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



English Language Learners Definition of prime (Entry 2 of 3)

: 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



English Language Learners Definition of prime (Entry 3 of 3)

: 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


\ ˈprīm \

Kids Definition of prime

 (Entry 1 of 3)

: the period in life when a person is best in health, looks, or strength



Kids Definition of prime (Entry 2 of 3)

: first in importance, rank, or quality Spring is a prime season to work outdoors.


primed; priming

Kids Definition of prime (Entry 3 of 3)

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.

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Legal Definition of prime

 (Entry 1 of 2)

primed; priming

Legal Definition of prime (Entry 2 of 2)

: to have priority over a perfected security interest primes an unperfected one

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More from Merriam-Webster on prime

Rhyming Dictionary: 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 Encyclopedia article about prime

Comments on prime

What made you want to look up prime? Please tell us where you read or heard it (including the quote, if possible).


to gather or build up little by little

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