Green and thick with healthy plant growth, or something luxurious and richly indulgent; also slang for a heavy drinker.
The adjective likely comes from Middle English or Old French 'lush,' possibly from a Germanic root meaning soft or tender. The drinking slang meaning appeared in the 1800s.
A 'lush green forest' and 'lush lifestyle' and 'lush drinker' are three very different meanings of the same word—one of the best examples of how the same word can drift to mean almost opposite things!
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