Real Dictionary

plug
countable noun: A plug is an electric socket.
countable noun: A plug on a piece of electrical equipment is a small plastic object with two or three metal pins which fit into the holes of an electric socket, connecting the equipment to the electricity supply.

plug in American English
an object used to stop up a hole, gap, outlet, etc.
to stop up or fill (a hole, gap, etc.) by inserting a plug
to work or study hard and steadily; plod
noun: 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

plug in Automotive Engineering 1
noun: A plug is a cap that stops pressure from leaking or being lost, for example in the cooling system of a vehicle.

plug in Automotive Engineering 2
noun: A plug is a small plastic object with metal pins inside that is inserted into a socket to connect two electrical parts in a vehicle together, for example the engine and the instrument panel.

plug in British English
noun: a piece of wood, cork, or other material, often cylindrical in shape, used to stop up holes and gaps or as a wedge for taking a screw or nail
verb: to stop up or secure (a hole, gap, etc) with or as if with a plug

plug in Electrical Engineering
noun: A plug is a small plastic device with two or three metal pins, that is intended to be attached to a flexible cable, and that fits into the holes of a socket outlet or with a connector.

plug in Hospitality 1
noun: A plug on a piece of electrical equipment is a small plastic object with two or three metal pins that fit into the holes of an electric outlet, allowing the equipment to connect to the electricity supply.

plug in Hospitality 2
noun: A plug is a thick, circular piece of rubber or plastic that you use to block the hole in a bathtub or sink when it is filled with water.

plug in the Oil and Gas Industry
noun: A plug is something, often cement, which is put across an opening to a formation to close it when a wellbore is being shut in.