pin

1. a small, slender, often pointed piece of wood, metal, etc., used to fasten, support, or attach things.

   Synonyms: peg, bolt

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.

   Synonyms: brooch

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.

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.

1. Digital Technology. to bookmark a photo or link on Pinterest:

   I've been pinning a lot lately.

verb phrase

1. to fill (gaps in a rubble wall, etc.) with spalls.
2. 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.

3. to make (a piece of masonry) level or plumb with wedges.

1. 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.