Dictionary.com
definitions

pin

[pin]
See more synonyms for pin on Thesaurus.com
noun
  1. a small, slender, often pointed piece of wood, metal, etc., used to fasten, support, or attach things.
  2. a short, slender piece of wire with a point at one end and a head at the other, for fastening things together.
  3. any of various forms of fasteners or ornaments consisting essentially or partly of a pointed or penetrating wire or shaft (often used in combination): a jeweled pin.
  4. a badge having a pointed bar or pin attached, by which it is fastened to the clothing: a fraternity pin.
  5. Digital Technology. a photo or link that is bookmarked on Pinterest, a website and mobile application: She added 5 pins to her recipes board.
  6. Machinery.
    1. a short metal rod, as a linchpin, driven through holes in adjacent parts, as a hub and an axle, to keep the parts together.
    2. a short cylindrical rod or tube, as a wrist pin or crankpin, joining two parts so as to permit them to move in one plane relative to each other.
    3. a short axle, as one on which a pulley rotates in a block.
  7. the part of a cylindrical key stem entering a lock.
  8. a clothespin.
  9. a hairpin.
  10. rolling pin.
  11. a peg, nail, or stud marking the center of a target.
  12. Bowling. any one of the rounded wooden clubs set up as the target in tenpins, ninepins, duckpins, etc.
  13. Golf. the flag staff which identifies a hole.
  14. any of the projecting knobs or rails on a pinball machine that serve as targets for the ball.
  15. Informal. a human leg.
  16. Music. peg(def 5).
  17. Wrestling. a fall.
  18. Nautical.
    1. an axle for a sheave of a block.
    2. belaying pin.
  19. Carpentry. a tenon in a dovetail joint; dovetail.
  20. a very small amount; a trifle: Such insincere advice isn't worth a pin.
  21. Chess. the immobilization of an enemy piece by attacking with one's queen, rook, or bishop.
  22. Electronics. a pin-shaped connection, as the terminals on the base of an electron tube or the connections on an integrated circuit.
verb (used with object), pinned, pin·ning.
  1. to fasten or attach with or as with a pin or pins: to pin two pieces of cloth together.
  2. to hold fast in a spot or position (sometimes followed by down): The debris pinned him down.
  3. to transfix or mount with a pin or the like: to pin a flower as a botanical specimen.
  4. Chess. to immobilize (an enemy piece) by placing one's queen, rook, or bishop in a position to check the exposed king or capture a valuable piece if the pinned piece were moved.
  5. Wrestling. to secure a fall over one's opponent.
  6. Digital Technology.
    1. to bookmark (a photo or link) on Pinterest, a website and mobile application: He pinned a jacket from Macy's on his fashion board.
    2. to fix (a social media post) to the top of a feed: She pinned a tweet about her forthcoming book to the top of her Twitter feed.
verb (used without object), pinned, pin·ning.
  1. Digital Technology. to bookmark a photo or link on Pinterest: I've been pinning a lot lately.
Verb Phrases
  1. pin down,
    1. to bind or hold to a course of action, a promise, etc.
    2. to force (someone) to deal with a situation or to come to a decision: We tried to pin him down for a definite answer, but he was too evasive for us.
  2. pin in, to fill (gaps in a rubble wall, etc.) with spalls.
  3. pin up, to make (a piece of masonry) level or plumb with wedges.
Idioms
  1. get pinned,
    1. (of a young woman) to receive a male student's fraternity pin as a symbol of his affection and fidelity, usually symbolizing that the couple is going steady or plans to become engaged.
    2. (of a young couple) to become formally pledged to one another, though not yet engaged, by the bestowing of such a pin or the exchange of pins.
  2. pin something on someone, Informal. to ascribe the blame or guilt for something to a person; show someone to be culpable: They pinned the crime on him.
  3. pull the pin, Informal. to end a relationship, project, program, or the like, because of lack of continuing interest, success, funds, etc.

Origin of pin

before 1100; (noun) Middle English pinne, Old English pinn “peg”; cognate with Dutch pin, German Pinne, Old Norse pinni; perhaps frrom Latin pinna “feather, quill” (see pinna); (verb) Middle English pinnen, derivative of the noun
Related formsre·pin, verb (used with object), re·pinned, re·pin·ning.

Synonyms for pin

See more synonyms for on Thesaurus.com
1. bolt, peg. 3. brooch.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

Related Words for pin down

reveal, express, pinpoint, show, suggest, signal, hint, mark, prove, imply, argue, announce, demonstrate, illustrate, make, specify, mean, unearth, detect, spot
British Dictionary definitions for pin down

pin down

verb (tr, adverb)
  1. to force (someone) to make a decision or carry out a promise
  2. to define clearlyhe had a vague suspicion that he couldn't quite pin down
  3. to confine to a placethe fallen tree pinned him down

PIN

n acronym for
  1. personal identification number: a number used by a holder of a cash card or credit card used in EFTPOS

pin

noun
    1. a short stiff straight piece of wire pointed at one end and either rounded or having a flattened head at the other: used mainly for fastening pieces of cloth, paper, etc, esp temporarily
    2. (in combination)pinhole
  2. short for cotter pin, hairpin, panel pin, rolling pin, safety pin
  3. an ornamental brooch, esp a narrow one
  4. a badge worn fastened to the clothing by a pin
  5. something of little or no importance (esp in the phrases not care or give a pin (for))
  6. a peg or dowel
  7. anything resembling a pin in shape, function, etc
  8. (in various bowling games) a usually club-shaped wooden object set up in groups as a target
  9. Also called: cotter pin, safety pin a clip on a hand grenade that prevents its detonation until removed or released
  10. nautical
    1. See belaying pin
    2. the axle of a sheave
    3. the sliding closure for a shackle
  11. music a metal tuning peg on a piano, the end of which is inserted into a detachable key by means of which it is turned
  12. surgery a metal rod, esp of stainless steel, for holding together adjacent ends of fractured bones during healing
  13. chess a position in which a piece is pinned against a more valuable piece or the king
  14. golf the flagpole marking the hole on a green
    1. the cylindrical part of a key that enters a lock
    2. the cylindrical part of a lock where this part of the key fits
  16. wrestling a position in which a person is held tight or immobile, esp with both shoulders touching the ground
  17. a dovetail tenon used to make a dovetail joint
  18. (in Britain) a miniature beer cask containing 4 1/2 gallons
  19. (usually plural) informal a leg
  20. be put to the pin on one's collar Irish to be forced to make an extreme effort
verb pins, pinning or pinned (tr)
  1. to attach, hold, or fasten with or as if with a pin or pins
  2. to transfix with a pin, spear, etc
  3. (foll by on) informal to place (the blame for something)he pinned the charge on his accomplice
  4. chess to cause (an enemy piece) to be effectively immobilized by attacking it with a queen, rook, or bishop so that moving it would reveal a check or expose a more valuable piece to capture
  5. Also: underpin to support (masonry), as by driving in wedges over a beam
See also pin down

Word Origin for pin

Old English pinn; related to Old High German pfinn, Old Norse pinni nail
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for pin down

pin

n.

late Old English pinn "peg, bolt," from Proto-Germanic *penn- "jutting point or peak" (cf. Old Saxon pin "peg," Old Norse pinni "peg, tack," Middle Dutch pin "pin, peg," Old High German pfinn, German Pinne "pin, tack") from Latin pinna "a feather, plume;" in plural "a wing;" also "fin, scoop of a water wheel;" also "a pinnacle; a promontory, cape; battlement" (e.g. in Luke iv:9 in Vulgate) and so applied to "points" of various sorts, from PIE *pet- (see pen (n.1)).

Latin pinna and penna "a feather, plume," in plural "a wing," are treated as identical in Watkins, etc., but regarded as separate (but confused) Latin words by Tucker and others, who derive pinna from PIE *spei- "sharp point" (cf. spike (n.1)) and see the "feather/wing" sense as secondary.

The modern slender wire pin is first attested by this name late 14c. Transferred sense of "leg" is recorded from 1520s and hold the older sense. Pin-money "annual sum allotted to a woman for personal expenses on dress, etc." is attested from 1620s. Pins and needles "tingling sensation" is from 1810. The sound of a pin dropping as a type of something all but silent is from 1775.

PIN

acronym for personal identification number, 1981, from the first reference used with redundant number.

pin

v.

mid-14c., "to affix with a pin," from pin (n.). Figurative use from 1570s. Related: Pinned; pinning. Sense of "to hold someone or something down so he or it cannot escape" is attested from 1740. In U.S., as a reference to the bestowal of a fraternity pin on a female student as an indication of a relationship, it is attested by 1938. Phrase pin down "define" is from 1951.

Online Etymology Dictionary, © 2010 Douglas Harper
pin down in Medicine

pin

[pĭn]
n.
  1. A thin rod for securing the ends of fractured bones.
  2. A peg for fixing the crown to the root of a tooth.
v.
  1. To fasten or secure with a pin or pins.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
Idioms and Phrases with pin down

pin down

1

Fix or establish clearly, as in The firefighters finally were able to pin down the source of the odor. [Mid-1900s]

2

Force someone to give precise information or opinions, as in The reporter pinned down the governor on the issue of conservation measures. [c. 1700]

pin

In addition to the idioms beginning with pin

  • pin back one's ears
  • pin down
  • pin money
  • pin on
  • pin one's heart on
  • pin one's hopes on
  • pin someone's ears back

also see:

  • hear a pin drop
  • on pins and needles
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.