[pahy-lee-uh s, pil-ee-]
- Mycology. the horizontal portion of a mushroom, bearing gills, tubes, etc., on its underside; a cap.
- the umbrella or bell of a jellyfish.
- Also called cap cloud, scarf cloud. Meteorology. a small, thin cloud just above or attached to a growing cumulus cloud.
- a felt skullcap worn by the ancient Romans and Greeks.
Origin of pileus
1750–60; < New Latin, special use of Latin pīleus skullcap; akin to Greek pîlos felt, felt cap
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for pileus
When the former, it is of the same consistency as the pileus.
The pileus is one to two inches broad and the stem is one to two and a half long.
The pileus is one to three inches broad; grows in dense tufts.
The stem is of the same color as the pileus, punctato-squamulose.
The stem is short and apparently the same color as the pileus.
- the upper cap-shaped part of a mushroom or similar spore-producing body
C18 (botanical use): New Latin, from Latin: felt cap
- The umbrellalike fruiting structure forming the top of a fleshy fungus. It is supported by the stipe. The cap of a mushroom is a pileus.
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