The definition of humongous is slang to describe something enormous or extremely large in size.(adjective)
A 20,000 square foot house is an example of a house that would be described as humongous.
See humongous in Webster's New World College Dictionary
Origin: prob. a blend and alteration of huge + monstrous
See humongous in American Heritage Dictionary 4
Origin: Perhaps blend of huge
Origin: and monstrous
Origin: or tremendous.
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