A person who drinks alcohol excessively or very frequently, especially someone who actively seeks out drinking opportunities. It's an informal, somewhat humorous or critical term.
From 'booze' (Middle Dutch 'buysen') + 'hound' (Old English 'hund'). The compound emerged in American slang in the early 1900s, using 'hound' in the sense of 'someone who hunts or pursues something eagerly.'
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