What is Plug?

Plug definition and meaning on Dictionary terms:
a piece of wood or other material used to stop up a hole or aperture, to fill a gap, or to act as a wedge.
a core or interior segment taken from a larger matrix.

Electricity. a device to which may be attached the conductors of a cord and which by insertion in a jack, or screwing into a receptacle, establishes contact.
spark plug(def 1).
a fireplug or hydrant.
a cake of pressed tobacco.
a piece of tobacco cut off for chewing.
Informal. the favorable mention of something, as in a lecture, radio show, etc.; advertisement; recommendation: The actress was happy to give her new show a plug.
Angling. an artificial lure made of wood, plastic, or metal, and fitted with one or more gang hooks, used chiefly in casting.
Geology. neck(def 14).
Slang. a worn-out or inferior horse.
Informal. a shopworn or unsalable article.
a small piece of sod used especially for seeding a lawn.
a patch of scalp with viable hair follicles that is used as a graft for a bald part of the head.Compare hair transplant.
Slang. punch1(def 1).
Metalworking. a mandrel on which tubes are formed. a punch on which a cup is drawn. a protrusion on a forging die for forming a recess in the work. a false bottom on a die.

Also called dook. a small piece of wood inserted into masonry as a hold for a nail.
Masonry. See under plug and feathers.
Also called plug hat. a man’s tall silk hat.

verb (used with object), plugged, plug