Dictionary
lem•ming
Pronunciation: (lem'ing), [key]—
n.
any of various small, mouselike rodents of the genera
Lemmus, Myopus, and
Dicrostonyx, of far northern regions, as
L. lemmus, of Norway, Sweden, etc., noted for periodic mass migrations that sometimes result in mass drownings.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.