1. N. An antique measurement of beer.

Example: Every man in this place could put away a homerkin if he didn’t have to pay for it himself.

I know. I know what you’re thinking, you modern child of the age. You think this word is supposed to signify someone who believes themselves to be a long-dead historian of the Greek persuasion, who discusses philosophy, medicine, and all the amazing things of antiquity, yes? 

No come now, that was a joke. You thought it referred to someone who believed themselves to be Homer Simpson. Admit it.

Seems somewhat fitting that it actually refers to drinking.