prime

Etymology 1

Borrowed from French prime, from Latin primus (“first”), from earlier prīsmos < *prīsemos < Proto-Italic *priisemos, ultimately from Proto-Indo-European *per- (“beyond, before”). Doublet of primo. The noun sense "apostrophe-like symbol" originates from the fact that the symbol ′ was originally a superscript Roman numeral one.

adj

1. First in importance, degree, or rank.
   Our prime concern here is to keep the community safe.
2. First in time, order, or sequence.
   Both the English and French governments established prime meridians in their capitals.
   The process of recording a transaction in the accounts begins with an entry in what is termed a book of prime entry. 2013, Ralph Denny, Accounts for Solicitors - Page 33
3. First in excellence, quality, or value.
   This is a prime location for a bookstore.
   Gemmen (says he), you all well know / The joy there is whene'er we meet; / It's what I call the primest go, / And rightly named, 'tis—'quite a treat,' […] 1820, Thomas Moore, W. Simpkin, R. Marshall, Jack Randall's Diary of Proceedings at the House of Call for Genius
   Average cost, 10d. to 18. per lb. for the primest parts. 1861, Isabella Beeton, Mrs Beeton's Book of Household Management
4. (mathematics, lay) Having exactly two integral factors: itself and unity (1 in the case of integers).
   Thirteen is a prime number.
5. (mathematics, technical) Such that if it divides a product, it divides one of the multiplicands.
6. (mathematics) Having its complement closed under multiplication: said only of ideals.
7. Marked or distinguished by the prime symbol.
8. Early; blooming; being in the first stage.
9. (obsolete) Lecherous, lewd, lustful.

noun

1. (historical) The first hour of daylight; the first canonical hour.
2. (Christianity) The religious service appointed to this hour.
3. (obsolete) The early morning generally.
4. (now rare) The earliest stage of something.
   1645, Edmund Waller, “To a very young Lady” (earlier title: “To my young Lady Lucy Sidney”) in Poems, &c. Written upon Several Occasions, and to Several Persons, London: H. Herringman, 1686, p. 101, Hope waits upon the flowry prime,
5. The most active, thriving, or successful stage or period.
   None but foreigners, excluded by their religion from the cemeteries of the country, are deposited here […]. The far greater part had been cut off in their prime, by unexpected disease or fatal accident. 1813, John Chetwode Eustace, chapter 10, in A Tour through Italy, volume 1, London: J. Mawman, pages 225–226
   Once upon a time you dressed so fine. You threw the bums a dime in your prime, didn’t you? 1965, Bob Dylan (lyrics and music), “Like a Rolling Stone”
   And it’s daunting because each segment has to tell a full, complete story in something like six minutes while doing justice to revered source material and including the non-stop laughs and genius gags that characterized The Simpsons in its god-like prime. April 29, 2012, Nathan Rabin, “TV: Review: THE SIMPSONS (CLASSIC): “Treehouse of Horror III” (season 4, episode 5; originally aired 10/29/1992)”, in (Please provide the book title or journal name)
6. The chief or best individual or part.
   Give him always of the prime; And but a little at a time. 1726, Jonathan Swift, “To a Lady, who desired the author to write some verses upon her in the heroic style” in The Works of Dr. Jonathan Swift, London: W. Bowyer et al., Volume 7, p. 396, Give no more to ev’ry guest Than he’s able to digest
7. (music) The first note or tone of a musical scale.
8. (fencing) The first defensive position, with the sword hand held at head height, and the tip of the sword at head height.
9. (algebra, number theory) A prime element of a mathematical structure, particularly a prime number.
   Some poems, echoing the purpose of early poetic treatises on scientific principles, attempt to elucidate the mathematical concepts that underlie prime numbers. Others play with primes’ cultural associations. Still others derive their structure from mathematical patterns involving primes. 2013 July-August, Sarah Glaz, “Ode to Prime Numbers”, in American Scientist, volume 101, number 4
   3 is a prime.
10. (card games) A four-card hand containing one card of each suit in the game of primero; the opposite of a flush in poker.
11. (backgammon) Six consecutive blocks, which prevent the opponent's pieces from passing.
    I'm threatening to build a prime here.
12. The symbol ′ used to indicate feet, minutes, derivation and other measures and mathematical operations.
13. (chemistry, obsolete) Any number expressing the combining weight or equivalent of any particular element; so called because these numbers were respectively reduced to their lowest relative terms on the fixed standard of hydrogen as 1.
14. An inch, as composed of twelve seconds in the duodecimal system.
15. (obsolete) The priming in a flintlock.
    […] he pull’d the Trigger, but Providence being pleas’d to preserve me for some other Purpose, the Cock snapp’d, and miss’d Fire. Whether the Prime was wet in the Pan, or by what other Miracle it was I escap’d his Fury, I cannot say […] 1743, Robert Drury, The Pleasant, and Surprizing Adventures of Mr. Robert Drury, during his Fifteen Years Captivity on the Island of Madagascar, London, pages 95–96
16. (film) Contraction of prime lens, a film lens.
    Tomlinson, Shawn M. (2015) Going Pro for $200 & How to Choose a Prime Lens, →ISBN: “By the time I shifted to my first autofocus film SLR with the Pentax PZ-10, primes were considered things of the past”
17. A feather, from the wing of the cock ostrich, that is of the palest possible shade.

Etymology 2

Related to primage and primus.

verb

1. (transitive) To prepare a mechanism for its main work.
   You'll have to press this button twice to prime the fuel pump.
2. (transitive) To apply a coat of primer paint to.
   I need to prime these handrails before we can apply the finish coat.
3. (obsolete, intransitive) To be renewed.
   Nights baſhfull Empreſſe, though ſhe often wayne, / As oft repents her darkneſſe ; primes againe ; / And with her circling Hornes does re-embrace / Her brothers wealth, and orbs her ſilver face. 1634, Francis Quarles, “My Soule Hath Desired Thee in the Night”, in Emblemes, London: G. M., published 1635, book III, page 129
4. (intransitive) To serve as priming for the charge of a gun.
5. (intransitive, of a steam boiler) To work so that foaming occurs from too violent ebullition, which causes water to become mixed with, and be carried along with, the steam that is formed.
   Although we took our eight bogies along to Whitstable at 60 m.p.h., and made a clean start from there, after Herne Bay the engine primed badly on Blacksole Bank and nearly stopped before we got over the top. Then we ran like the wind across the marshes with half-regulator, 30 per cent cut-off, and the engine blowing off. 1959 April, P. Ransome-Wallis, “The Southern in Trouble on the Kent Coast”, in Trains Illustrated, London: Ian Allan Publishing, →ISSN, →OCLC, page 220
6. To apply priming to (a musket or cannon); to apply a primer to (a metallic cartridge).
7. To prepare; to make ready; to instruct beforehand; to coach.
   to prime a witness
   The boys are primed for mischief.
8. (UK, dialect, obsolete) To trim or prune.
   to prime trees
9. (mathematics) To mark with a prime mark.

Etymology 3

From French prime (“reward, prize, bonus”).

noun

1. (cycling) An intermediate sprint within a race, usually offering a prize and/or points.
   Most primes are won with gaps on the field; most sprints are in bunches. 1997, Arnie Baker, Smart Cycling: Successful Training and Racing for Riders of All Levels