plug

an old or over-worked horse

an upright hydrant for drawing water to use in fighting a fire

blockage consisting of an object designed to fill a hole tightly

an electrical device with two or three pins that is inserted in a socket to make an electrical connection

electrical device that fits into the cylinder head of an internal-combustion engine and ignites the gas by means of an electric spark

blatant or sensational promotion

a wad of something chewable as tobacco

insert as a plug

She plugged a cork in the wine bottle

insert a plug into

plug the wall

persist in working hard

Students must plug away at this problem

make a plug for; praise the qualities or in order to sell or promote

deliver a quick blow to

he punched me in the stomach