prime

Less common meanings

6. 6
   two-factor numbernouncountable

   An element of a mathematical structure with no nontrivial divisors, most familiarly a whole number divisible only by one and itself.

   Eleven is a prime, while twelve breaks down into two, two, and three.

   The sieve of Eratosthenes is a simple way to list small primes.

   Note

   The noun is the prime-number adjective with its noun absorbed. A prime number becomes simply a prime, and it counts like any noun: three is a prime, the small primes, "primes' cultural associations," as Sarah Glaz writes in American Scientist (2013). Algebra stretches it to prime elements in general, but most often it means a whole number. Source

   Checked 1 Nov 2026 · 2 facts

   • The mathematical noun prime is a shortening of prime number. cip.ifi.lmu.de
   • Sarah Glaz used the words “primes’ cultural associations” in American Scientist in 2013. www2.math.uconn.edu
7. 7
   base coatverbtransitive

   To apply a coat of primer paint to a surface in preparation for the final coats.

   The crew primed the bare drywall before the first finish coat.

   Always prime new wood so the paint adheres evenly.

   Similarundercoat

8. 8
   verbtransitive

   To fill or prepare the chamber of a device so that it is ready for its main task.

   Before pulling the cord, he primed the mower by pressing the rubber bulb.

   You have to prime an old well pump with water before it will draw anything up.

   UsageThe object names the device or part being prepared: prime the pump, prime the engine, prime the line.

   Similarcharge, fill

9. 9
   starting pointadjective

   First in time, order, or sequence; coming before all the rest.

   Philosophers debated whether motion required a prime mover that started everything.

   The prime meridian sets the starting point from which longitude is counted.

   UsageMostly in set phrases: prime mover, prime meridian, prime cause.

   Similarfirst, original, earliest

   Oppositelast, final

   Note

   Accountants speak of a book of prime entry, where a transaction is first recorded. Milton's Samson Agonistes (1671) has a prime cause, and Tennyson's The Princess (1847) clears prime forests, meaning original, first-growth woods. Read prime cause as "first in the chain," not as the "most important" meaning, though the two often overlap. Source

   Checked 2 Nov 2026 · 6 facts

   • A book of prime entry is where an accounting transaction is initially recorded. accaglobal.com
   • Samson Agonistes is by John Milton, and its first edition bears the year 1671. christs.cam.ac.uk
   • Samson Agonistes contains prime cause; Samson speaks the words. en.wikisource.org
   • The Princess is by Alfred Tennyson and was first published in 1847. en.wikisource.org
   • The Princess contains the phrase clear prime forests, spoken by Cyril. en.wikisource.org
   • The cited prime cause and prime forests examples illustrate the sense first or original. en.wiktionary.org
10. 10
    lead companynouncountable

    A business or organization that ranks first in importance or standing, such as a lead defense contractor or major mortgage lender.

    The agency selected an established prime to oversee the entire weapons program.

    The big defense primes hand out much of their work to smaller companies.

    UsageOften plural with a size word: the big primes, the large primes.

    Note

    A House Select Committee on Small Business hearing (1966) and The Wall Street Journal (2023) both use it to set the leading firms apart from the smaller companies that work under them or compete with them. Source

    Checked 2 Nov 2026 · 2 facts

    • A House Select Committee on Small Business hearing publication dated 1966 uses “big primes” for the leading contractors. en.wiktionary.org
    • The Wall Street Journal used “large primes” in 2023 when contrasting established defense contractors with the startup Anduril. en.wiktionary.org
11. 11
    fixed lensnounabbreviationcontraction

    Short form of prime lens: a camera lens with a single fixed focal length, as opposed to a zoom.

    He swapped the zoom for a sharp prime before the close-up shots.

    Their kit included a row of primes covering every common focal length.

    Note

    A clipping used by photographers and filmmakers as an ordinary countable noun: a prime, a set of primes. It stands opposite the zoom, one fixed focal length against a range of them. Shawn M. Tomlinson's Going Pro for $200 (2015) recalls that, by the time he moved to his first autofocus film SLR, "primes were considered things of the past." Source

    Checked 1 Nov 2026 · 3 facts

    • Prime lenses have one fixed focal length, whereas zoom lenses have an adjustable focal length. rooseveltextension.nmsu.edu
    • The quoted words are attributed to Shawn M. Tomlinson; the cited work's full title is Going Pro for $200 & How to Choose a Prime Lens. en.wiktionary.org
    • He refers to his own switch to his first autofocus film SLR, a Pentax PZ-10, rather than the introduction of autofocus film SLRs. en.wiktionary.org
12. 12
    nouncountable

    A small raised stroke (′) that stands for feet or minutes, marks a derivative, and serves in various other measurements and mathematical notations.

    In her notes, a single prime after the variable marked the first derivative.

    The surveyor added a prime to the figure to record it in feet.

13. 13
    adjective

    Bearing or distinguished by the prime symbol (′), used to mark a related but distinct quantity.

    In the moving frame, the time is written as t prime instead of t.

    The reflected triangle is labeled A prime B prime C prime.

    UsageComes after the letter it marks: x prime, A prime.

14. 14
    verbtransitive

    To apply priming powder to a musket or cannon, or fit a primer into a cartridge, so it will ignite; of powder, to serve as the priming that sets off the main charge.

    Gunners would prime the cannon with fine powder before the order to fire.

    The reloader primed each cartridge before seating the bullet.

15. 15
    divides a factoradjective

    Of a number or element that is neither zero nor a unit, such that whenever it divides a product, it divides at least one of the factors.

    A prime element divides one of the factors whenever it divides their product.

    In any ring, a nonzero element that is not a unit is prime if it always divides a factor of any product it divides.

    Note

    The technical form of primeness is stated in terms of division rather than factors, so it applies to elements of structures other than the integers. Among whole numbers it singles out the familiar primes of the schoolroom definition. Its advantage is that "divides a product" makes sense wherever multiplication does. Source

    Checked 1 Nov 2026 · 2 facts

    • Technical primeness uses a product-divisibility condition and applies beyond the integers. crypto.stanford.edu
    • Divisibility can be expressed using multiplication, allowing the product-divisibility condition to extend to other multiplicative structures. mathe2.uni-bayreuth.de
16. 16
    nounhistoricaluncountable

    The first hour of daylight, reckoned from sunrise; also the canonical hour following lauds, or the Christian service appointed for that hour and recited in the early morning.

    Medieval monks sang prime at sunrise, soon after the earlier service of lauds.

    His larum bell might lowd and wyde be hard, When cause requyrd, but neuer out of time; Early and late it rong, at euening and at prime.

    1590, Edmund Spenser, The Faerie Queene

    UsageUsually no article: monks sang prime, the bell rang for prime.

    Note

    It belongs mainly to writing about the medieval and Renaissance world, though Eastern and Coptic churches and some monastic communities still pray an office of this name. Spenser's Faerie Queene (1590) rings a bell "at euening and at prime," pairing it with evening as the two ends of the day. Source

    Checked 2 Nov 2026 · 3 facts

    • Edmund Spenser wrote The Faerie Queene, whose first three books appeared in 1590. gla.ac.uk
    • The first-edition title page bears the date 1590. talus.artsci.wustl.edu
    • The poem describes a bell ringing 'at euening and at prime', pairing evening with early morning. gutenberg.org
17. 17
    add tick markverbtransitive

    To mark a symbol, letter, or number with the prime sign (′).

    When the value shifts, we prime the variable and write x′.

    She primed each coordinate to distinguish the rotated figure from the original.

18. 18
    ring idealadjective

    Of a proper ideal in a commutative ring: such that the complement of the ideal is closed under multiplication.

    An ideal is prime when the product of two elements outside it also lies outside it.

    In the integers, the prime ideals are generated by the prime numbers and zero.

    Note

    Said of a proper ideal in a commutative ring, its condition reads more easily turned around: if a product of two elements falls inside the ideal, at least one of the elements was already there. That is the divisibility test of prime elements, moved from single elements to whole ideals. In the integers the prime ideals come from the prime numbers, together with zero. Source

    Checked 1 Nov 2026 · 3 facts

    • For a proper ideal in a commutative ring, this is the prime-ideal test. Properness is essential: the whole ring also satisfies the stated product condition but is not a prime ideal. maths.dur.ac.uk
    • The product-membership test generalizes the divisibility property of prime elements. ocw.mit.edu
    • The prime ideals of the integers are the ideals generated by prime numbers and the zero ideal. legacy-www.math.harvard.edu
19. 19
    algebra moduleadjective

    Of a module, having the property that every nonzero submodule has exactly the same annihilator as the module as a whole.

    A module is prime when every nonzero submodule shares the same annihilator as the module itself.

    Prime modules generalize the notion of a prime ideal to module theory.

    Note

    Module theory's version of the idea, applied only to nonzero modules. No nonzero piece of the module is annihilated by more of the ring than the whole module is. The condition extends the prime ideal to modules and keeps the word because it plays the same role there. Source

    Checked 1 Nov 2026 · 2 facts

    • Prime modules are nonzero, and every nonzero submodule has the same annihilator as the whole module. journals.iugaza.edu.ps
    • The condition extends the prime-ideal concept to modules; the stated naming rationale is supported as a mathematical analogy. c-negron.github.io
20. 20
    nounarchaic

    The chief or best individual or part within a larger whole.

    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…
21. 21
    adjectivearchaic

    Being in the early, fresh, blooming first stage of growth or life.
22. 22
    noun

    A stimulus that causes priming, influencing how a person responds to related information shortly afterward.
23. 23
    noundated

    The first note or tone on which a musical scale begins.
24. 24
    noun

    An intermediate sprint within a race, usually offering a prize or points to the rider who wins it.
25. 25
    noun

    In fencing, the first defensive guard or parry, with the wrist turned over, the hand raised, and the blade pointing down to cover the inside line.
26. 26
    noun

    In backgammon, a series of consecutive occupied points forming a wall that blocks the opponent's pieces from advancing.
27. 27
    noun

    In the card game primero, a four-card hand holding exactly one card of each of the four suits: the reverse of a poker flush.
28. 28
    adjectiveobsolete

    Full of sexual desire, randy.
29. 29
    nounobsolete

    The first hours after dawn, considered broadly.
30. 30
    nounarchaic

    The beginning phase of anything, when it is new.

    To this end we see how quickly sundry artes Mechanical were found out in the very prime of the world.

    1594, Richard Hooker, Of the Lawes of Ecclesiastical Politie
31. 31
    nounobsolete

    A number in older chemistry giving an element's equivalent weight, the amount that combines with or replaces one part of hydrogen.
32. 32
    noun

    An inch, regarded in the duodecimal system as made up of twelve smaller units.
33. 33
    nounobsolete

    The powder in the pan of a flintlock that ignites the main charge.
34. 34
    noun

    A wing feather of a male ostrich that is as light in color as possible.
35. 35
    verbobsolete

    To become new or fresh again.

    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”
36. 36
    verb

    Of a steam boiler, to boil so violently that it foams and sends water out mixed into the steam.
37. 37
    verbobsoleteUK

    To cut back branches or shoots of a plant.