Bottoms up!

bottoms up

A cheerful phrase or toast said before taking a drink. Ooh, that drink looks delicious—bottoms up!
See also: bottom, up
Farlex Dictionary of Idioms.

Bottoms up!

 and Here's looking at you.; Here's mud in your eye.; Here's to you.
Inf. an expression said as a toast when people are drinking together. (Alludes to the bottoms of the drinking glasses.) Bill: Bottoms up. Tom: Here's mud in your eye. Bill: Ah, that one was good. Care for another?
See also: Bottom
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

bottoms up!

used to express friendly feelings towards your companions before drinking. informal
The expression refers to the raising of a glass towards the horizontal.
See also: bottom
Farlex Partner Idioms Dictionary

bottoms ˈup!

(old-fashioned, spoken) used for telling people to finish their drinks, or to express good wishes when drinking alcohol: Come on everybody, it’s time to go home. Bottoms up!
See also: bottom
Farlex Partner Idioms Dictionary
See also:
  • bottoms up
  • into the drink
  • be in the drink
  • What's your poison?
  • What are you drinking?
  • What are you having?
  • What would you like to drink?
  • name your poison
  • nectar of the gods
  • drink to (someone's or something's) health