Noun

1. A drinking vessel filled to the brim.
   • 1749, Henry Fielding, Tom Jones, Folio Society 1973, p. 443:

     they now shook hands heartily, and drank bumpers of strong beer to healths which we think proper to bury in oblivion.

2. Anything large or successful (now usually attributively).
3. Parts at the front and back of a vehicle which are meant to absorb the impact of a collision.
4. Any mechanical device used to absorb an impact, soften a collision, or protect against impact.
   • The company sells screw-on rubber bumpers and feet.
5. Someone or something that bumps.
6. A bouncer.
7. A side wall of a pool table.
8. A short ditty or jingle used to separate a show from the advertisements.

Adjective

1. Large; filled to the bumpers at the top of a silo.
   • We harvested a bumper crop of arugula and parsnips this year.