bumper

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A usually metal or rubber bar attached to either end of a motor vehicle, such as a truck or car, to absorb impact in a collision.
2. n. A protective device for absorbing shocks or impeding contact.
3. n. A drinking vessel filled to the brim.
4. n. Something extraordinarily large.
5. adj. Extraordinarily abundant or full: a bumper crop of corn.

Century Dictionary and Cyclopedia

1. n. One who or that which bumps.
2. n. A log of wood placed over a ship's side to keep off ice, or anything similarly used; a fender.
3. n. A cup or glass filled to the brim, especially when drunk as a toast.
4. n. A crowded house at a theatrical benefit, or the like.
5. To fill to the brim.
6. n. A species of pompano-like fish, Chloroscombrus chrysurus, of the family Carangidæ, found on the South Atlantic coast and about Cuba. Also called casabe.
7. n. In felt-hat manuf., a machine used for consolidating the felted material.
8. n. In Eng. whist, a rubber of 8 points.
9. Brimming; abundant; very good; as, a bumper crop.
10. To toast by drinking off a bumper.
11. To drink bumpers: as, “we all sang and bumpered away,”
12. n. In pianoforte-making, same as counter-check, 2.

Wiktionary

1. n. A drinking vessel filled to the brim.
2. n. Anything large or successful (now usually attributively).
3. n. Parts at the front and back of a vehicle which are meant to absorb the impact of a collision; fender
4. n. Any mechanical device used to absorb an impact, soften a collision, or protect against impact
5. n. Someone or something that bumps.
6. n. A bouncer.
7. n. A side wall of a pool table.
8. n. A short ditty or jingle used to separate a show from the advertisements.
9. adj. Large; filled to the bumpers at the top of a silo.

GNU Webster's 1913

1. n. A cup or glass filled to the brim, or till the liquor runs over, particularly in drinking a health or toast.
2. n. A covered house at a theater, etc., in honor of some favorite performer.
3. n. That which bumps or causes a bump.
4. n. Anything which resists or deadens a bump or shock, such as a metal or rubber rim extending from an object; a buffer.
5. n. a protective guard device, usually of metal or rubber, attached horizontally to the front or rear of the frame of a vehicle, designed to resist or deaden a bump or shock, and to prevent damage to the main frame of the vehicle in low-velocity collisions.

WordNet 3.0

1. n. a glass filled to the brim (especially as a toast)
2. n. a mechanical device consisting of bars at either end of a vehicle to absorb shock and prevent serious damage