noun
large amount of alcohol; heavy drinking
Refers to drinking a large quantity of alcohol in one sitting or habitually. Often used in phrases like 大酒を飲む.
彼は毎晩大酒を飲んでいる。
He drinks heavily every night.
noun
Can refer to a person who habitually drinks a lot. Often used with ～だ or ～である.
あの人は大酒だから、一緒に飲むと大変だ。
That person is a heavy drinker, so it's tough to drink with them.
Compound of 大 (おお, 'big, large') and 酒 (さけ, 'alcohol, sake'). The reading おおざけ is a straightforward combination.