What's the word for contents that are left in glass after a drink is finished? [closed]

What's the word the contents that are left in the glass after a drink is finished?

eg:

'He drained his glass to the ______'


Dregs - The dregs of a liquid are the last drops left at the bottom of a container, together with any solid bits that have sunk to the bottom.

As noted this isn't limited to the contents of a glass (i.e. the container could be a bottle or cup, etc.)