an obstruction in a pipe or tube

close or secure with or as if with a stopper

a plug used to close a hole in a barrel or flask

the plug in the mouth of a bottle (especially a wine bottle)

a removable plug for holding water in a tub or basin

a plug of cotton, wax, or rubber that is fitted into the ear canal for protection against the entry of water or loud noise

a wooden plug forming a flue pipe (as the mouthpiece of a recorder)