The Collaborative International Dictionary of English v.0.48:
Kitchen middens \Kitch"en mid`dens\ (k[i^]ch"[e^]n m[i^]d`d'nz)
n. pl. [Dan. kj["o]k-kenm["o]ddings kitchen leavings; cf.
Scot. midden a dunghill.]
Relics of neolithic man found on the coast of Denmark,
consisting of shell mounds, some of which are ten feet high,
one thousand feet long, and two hundred feet wide. The name
is applied also to similar mounds found on the American coast
from Canada to Florida, made by the North American Indians.