plug

an old or over-worked horse

persist in working hard

“Students must plug away at this problem”

insert a plug into

“plug the wall”

insert as a plug

“She plugged a cork in the wine bottle”

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

replace the center of a coin with a baser metal

“plug a nickle”

blockage consisting of an object designed to fill a hole tightly

blatant or sensational promotion

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

deliver a quick blow to

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

fill or close tightly with or as if with a plug

“plug the hole”