Synonyms for Stopper:

n.

cap, compartment, fill, full, lid, lip, mouth, overflow, flip top. closure (noun)
choke, closure, fastener, lock, obstruction, seal.
plug (noun)
bung, cork, cover, fill, lid, plug, spigot, spile, stop, stopple, tap, valve.
stopper (noun)
conversation stopper, plug, show-stopper, stopple.

v.

contact (verb)
stopple.

Other synonyms:

cap. fill. stop up
plug.
Other relevant words:
bung, cap, conversation stopper, fill, lid, show-stopper, stopple.

Usage examples for stopper

  1. Colleville tried by a few jovialities to raise the temperature of the assemblage; but the coarse salt of his witticisms had an effect, in the atmosphere in which he produced them, of a loud laugh in a sick- chamber; and a mute intimation from his wife, Thuillier, and la Peyrade to behave himself put a stopper on his liveliness and turbulent expansion. – The Lesser Bourgeoisie by Honore de Balzac
  2. He had no choice but to walk up to the medicine bottle whose stopper was out. – Lonesome Town by Ethel and James Dorrance
  3. You put the stopper on to that intention. – The Dark Tower by Phyllis Bottome