pin (redirected from hearing a pin drop)

pin. One of the earliest human artifacts, pins were at first made of thorns, bone, or wood and were used as clothing fasteners, hairpins, and meat skewers. These long, single-shaft pins were early imitated in metal and were often tipped with ornamental knobs. The fibulae, prototype of the safety pin and probably one of the earliest applications of the spring coil, was popular from early antiquity through medieval times. It was the forerunner of the modern brooch through the hinged pin, which was developed by the Romans. Bent-wire hairpins are believed to have originated in England in the 16th cent.; the modern bobby pin was introduced in the 20th cent. In the 14th and 15th cent. in England the costliness and scarcity of plain pins caused Parliament to limit their sale to the first two days of January, for which women saved money all year—hence the term "pin money." In the 19th cent., with the fashion for enormous hats came the development of ornate jeweled hatpins.

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pin (fastener)

In mechanical and civil engineering, a peg or bar designed to fasten machine and structural components together or to keep them aligned. Dowel pins are used to keep machine components aligned, sometimes without making a rigid joint (as in a pin-connected truss). Taper pins are used to fix the hub of a gear or a pulley to a shaft. Split cotter pins prevent nuts from turning on bolts and keep loosely fitting pins in place. The clevis pin has a ridge at one end and is kept in place by a cotter pin inserted through a hole in the other end. Many other types of pins are used in various machines.

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pin

(1) The male lead on a chip or cable connector (serial cable, keyboard cable, etc.). Each pin is plugged into its female counterpart to complete the circuit. The number of pins reflects the number of wires, or pathways, that can carry signals.

(2) (PIN) (Personal Identification Number) A password used for identification. The term came from the banking industry. See password.

(3) (PIN) (Processor Independent NetWare) A version of NetWare 4.1 designed for portability to multiple platforms. Development was stopped in early 1995.

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pin

1. short for cotter pin hairpin panel pin rolling pin, safety pin

2. (in various bowling games) a usually club-shaped wooden object set up in groups as a target

3. Nautical

a. See belaying pin

b. the axle of a sheave

c. the sliding closure for a shackle

4. 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

5. Surgery a metal rod, esp of stainless steel, for holding together adjacent ends of fractured bones during healing

6. Chess a position in which a piece is pinned against a more valuable piece or the king

7. Golf the flagpole marking the hole on a green

8. 

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

9. Wrestling a position in which a person is held tight or immobile, esp with both shoulders touching the ground

10. (in Britain) a miniature beer cask containing 4½ gallons

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PIN - Personal Identification Number