bumper

noun

1. a glass filled to the brim (especially as a toast)

   noun.artifact

   Examples

   We quaffed a bumper of ale.

   Source: WordNet 3.0

2. a mechanical device consisting of bars at either end of a vehicle to absorb shock and prevent serious damage

   noun.artifact

   Source: WordNet 3.0

3. A cup or glass filled to the brim, or till the liquor runs over, particularly in drinking a health or toast.

   noun

   Source: webster1913

4. That which bumps or causes a bump.

   noun

   Source: webster1913