1707, "abounding in lumps," from lump (n.) + -y (2). In early 19c. slang, "drunk." Among sailors, of the sea when forming small waves in rough water, from 1857. Related: Lumpiness.
lumpy gravy
lummox
lump
lumpectomy
lumpenproletariat
lumpish
lumpy
luna
lunacy
lunar
Lunarian
lunate