Dictionary
pi•le•us
Pronunciation: (pī'lē-us, pil'ē-), [key]—
n.,
—pl. pi•le•iPronunciation: (pī'lē-ī", pil'ē-ī") [key] for 1, 2, 4, pi•le•us for 3.
1. Mycol.the horizontal portion of a mushroom, bearing gills, tubes, etc., on its underside; a cap. See diag. under
mushroom.
2. Zool.
a. the umbrella or bell of a jellyfish.
b. pileum.
3. Also called
cap cloud, scarf cloud. Meteorol.a small, thin cloud just above or attached to a growing cumulus cloud.
4. a felt skullcap worn by the ancient Romans and Greeks.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.