pin (Noun) — A small slender (often pointed) piece of wood or metal used to support, fasten or attach things.
pin (Noun) — A piece of jewellery that is pinned onto the wearer's garment.
pin (Noun) — When a wrestler's shoulders are forced to the mat.
pin (Noun) — A small marker inserted into a surface to mark scores or define locations etc..
pin (Noun) — Informal term for the leg. ex. "fever left him weak on his pins"
pin (Noun) — Axis consisting of a short shaft that supports something that turns.
pin (Noun) — Cylindrical tumblers consisting of two parts that are held in place by springs; when they are aligned with a key the bolt can be thrown.
pin (Noun) — Flagpole used to mark the position of the hole on a golf green.
pin (Noun) — A holder attached to the gunwale of a boat that holds the oar in place and acts as a fulcrum for rowing.
pin (Noun) — A club-shaped wooden object used in bowling; set up in triangular groups of ten as the target.
pin (Noun) — A number you choose and use to gain access to various accounts.
pin (Verb) — To hold fast or prevent from moving. ex. "The child was pinned under the fallen tree"
pin (Verb) — Attach or fasten with pins or as if with pins. ex. "pin the needle to the shirt". "pin the blame on the innocent man"
pin (Verb) — Pierce with a pin. ex. "pin down the butterfly"
pin (Verb) — (chess) immobilize a piece.