What is "best bitter"

Usage examples of "best bitter".

Exuberance and Hall and Woodhouse best bitter was a mixture to be wary of, but one of the first effects it had is to stop you being wary of things, and the point at which Arthur should have stopped and explained no more was the point at which he started instead to get inventive.

The barmaid named Daphne set pints of what was misleadingly called best bitter in front of David Goldfarb and Jerome Jones.

What they call best bitter's gone to the dogs since the war (gone through their kidneys, by the taste of it), but there's always Daphne to stare at, maybe even to chat up.