A women who has a tireless appetite for boozing and is not only very good at it but is also much fun to be around. Subject may also be described as being just like 'one of the boys'. A term of endearment.
Off to the pub later, I think Mandy is going to tag along, she is a real booze hag.
Booze Hag; is a wife that does nothing but drink from sun up to, well, sun up. Only care about the bottle and making sure the bottom is seen after a good time of drinking and getting it on with other men besides her husband.
full time drinker that bitch Sandy that is a GREAT BOOZE HAG