a small, slender, often pointed piece of wood, metal, etc., used to fasten, support, or attach things.
a short, slender piece of wire with a point at one end and a head at the other, for fastening things together.
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.
a badge having a pointed bar or pin attached, by which it is fastened to the clothing: a fraternity pin.
a short metal rod, as a linchpin, driven through holes in adjacent parts, as a hub and an axle, to keep the parts together.
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.
a short axle, as one on which a pulley rotates in a block.
the part of a cylindrical key stem entering a lock.
a clothespin.
a hairpin.
a peg, nail, or stud marking the center of a target.
Bowling. any one of the rounded wooden clubs set up as the target in tenpins, ninepins, duckpins, etc.
Golf. the flag staff which identifies a hole.
any of the projecting knobs or rails on a pinball machine that serve as targets for the ball.
Informal. a human leg.
Music. peg ( def 5 ).
Wrestling. a fall.
an axle for a sheave of a block.
Carpentry. a tenon in a dovetail joint; dovetail.
a very small amount; a trifle: Such insincere advice isn't worth a pin.
Chess. the immobilization of an enemy piece by attacking with one's queen, rook, or bishop.
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, pinning.
to fasten or attach with or as with a pin or pins: to pin two pieces of cloth together.
to hold fast in a spot or position (sometimes followed by down ): The debris pinned him down.
to transfix or mount with a pin or the like: to pin a flower as a botanical specimen.
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.
Wrestling. to secure a fall over one's opponent.
Verb phrases
pin down,
to bind or hold to a course of action, a promise, etc.
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.
pin in, to fill (gaps in a rubble wall, etc.) with spalls.
pin up, to make (a piece of masonry) level or plumb with wedges.
get pinned,
(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.
(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.
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.
pull the pin, Informal. to end a relationship, project, program, or the like, because of lack of continuing interest, success, funds, etc.

before 1100; (noun) Middle English pinne, Old English pinn peg; cognate with Dutch pin, German Pinne, Old Norse pinni; perhaps < Latin pinna feather, quill (see pinna); (v.) Middle English pinnen, derivative of the noun

repin, verb (used with object), repinned, repinning.

1. bolt, peg. 3. brooch. Unabridged


noun Computers.
a number assigned to an individual, used to establish identity in order to gain access to a computer system via an automatic teller machine, a point-of-sale terminal, or other device.

p(ersonal) i(dentification) n(umber) Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2014.
Cite This Source Link To pin
World English Dictionary
pin (pɪn)
1.  a.  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
 b.  (in combination): pinhole
2.  cotter pin hairpin panel pin rolling pin short for 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 careorgive 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.  cotter pin, Also called: safety pin a clip on a hand grenade that prevents its detonation until removed or released
10.  nautical
 a.  See belaying pin
 b.  the axle of a sheave
 c.  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
15.  a.  the cylindrical part of a key that enters a lock
 b.  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 4½ gallons
19.  informal (usually plural) a leg
20.  (Irish) be put to the pin on one's collar to be forced to make an extreme effort
vb , pins, pinning, pinned
21.  to attach, hold, or fasten with or as if with a pin or pins
22.  to transfix with a pin, spear, etc
23.  informal (foll by on) to place (the blame for something): he pinned the charge on his accomplice
24.  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
25.  Also: underpin to support (masonry), as by driving in wedges over a beam
[Old English pinn; related to Old High German pfinn, Old Norse pinni nail]

PIN (pɪn)
n acronym for
personal identification number: a number used by a holder of a cash card or credit card used in EFTPOS

Collins English Dictionary - Complete & Unabridged 10th Edition
2009 © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009
Cite This Source
Word Origin & History

late O.E. pinn "peg, bolt," from P.Gmc. *penn- "jutting point or peak" (cf. O.N. pinni "peg, tack," M.Du. pin "pin, peg," O.H.G. pfinn, Ger. Pinne "pin, tack") which may be via L. pinna "wing, feather," also used for "pointed peak," from PIE *bend- "something protruding." The modern slender wire pin
is first attested by this name c.1380. Transferred sense of "leg" is recorded from 1530. The verb is recorded from c.1300; sense of "to hold someone or something down so he or it cannot escape" is attested from 1740. Pin-up (adj.) is from 1941 (first in ref. to Dorothy Lamour); the noun is recorded from 1943. Pinwheel is from 1696, "a wheel in the striking train of a clock in which pins are fixed to lift the hammer;" fireworks sense is from 1869. Pinhead "person of small intelligence" is first attested 1896. Pin-stripe is attested from 1896. Pin-money "annual sum allotted to a woman for personal expenses on dress, etc." is attested from 1621.

acronym for personal identification number, 1981, from the first ref. used with redundant number.
Online Etymology Dictionary, © 2010 Douglas Harper
Cite This Source
American Heritage
Medical Dictionary

pin (pĭn)

  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. pinned, pin·ning, pins
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.
Cite This Source
Computing Dictionary

PIN definition

Personal Identification Number

The Free On-line Dictionary of Computing, © Denis Howe 2010
Cite This Source
American Heritage
Abbreviations & Acronyms
personal identification number
The American Heritage® Abbreviations Dictionary, Third Edition
Copyright © 2005 by Houghton Mifflin Company.
Published by Houghton Mifflin Company. All rights reserved.
Cite This Source
American Heritage
Idioms & Phrases


In addition to the idioms beginning with pin, also see hear a pin drop; on pins and needles.

The American Heritage® Dictionary of Idioms by Christine Ammer.
Copyright © 1997. Published by Houghton Mifflin.
Cite This Source
Example sentences for pin
Pin stands for personal identification number, obviating the second word in pin
Tollers need to be brushed with a pin brush and slicker once to twice a week.
The binary value expressed on these selector pins determines the selected input
His routine was to come in, run around to his theme song and burst his head
  with a pin.
Copyright © 2014, LLC. All rights reserved.
  • Please Login or Sign Up to use the Recent Searches feature