The definition of a lump is a mass of stuff with no definite shape, a swelling underneath the skin or to a person who is dull-witted.(noun)
To lump is defined as to group things together, even if they don't necessarily all belong together.(verb)
When you meet one person and decide his whole family is just like him, this is an example of a situation where you lump the family together.
See lump in Webster's New World College Dictionary
Origin: ME lompe, lumpe, akin ? to Dan lompe, a mass, lump, Swed dial. lump, a block, stump, MHG lumpe, rag: see limp
Origin: Early ModE, to look sour < ? lump, but infl. by grump, mump
See lump in American Heritage Dictionary 4
Origin: Middle English lumpe
Origin: , of Low German origin
Origin: ; akin to obsolete Dutch lompe.
transitive verb lumped, lump·ing, lumps
Origin: Perhaps from dialectal lump, to look sullen.
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