• WordNet 3.6
    • n pileus a fruiting structure resembling an umbrella or a cone that forms the top of a stalked fleshy fungus such as a mushroom
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Webster's Revised Unabridged Dictionary
    • Pileus (Rom. Antiq) A kind of skull cap of felt.
    • Pileus (Bot) The expanded upper portion of many of the fungi. See Mushroom.
    • Pileus (Zoöl) The top of the head of a bird, from the bill to the nape.
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Century Dictionary and Cyclopedia
    • n pileus Among the ancient Romans, a conical cap or hat of felt; a cap or skullcap.
    • n pileus In botany, the expanded cap-like or umbrella-like summit of the stipe, bearing the hymenium, in hymenomycetous fungi: same as cap, 2 . See cuts under Agaricus and Fungi.
    • n pileus In ornithology, same as pileum.
    • n pileus [capitalized] [NL.] A genus of echinoderms.
    • n pileus A nipple-shield.
    • n pileus The disk or umbrella of a jellyfish.
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Chambers's Twentieth Century Dictionary
    • n Pileus pil′ē-us a Roman conical cap:
    • n Pileus pil′ē-us (bot.) the summit of the stipe bearing the hymenium in some fungi
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Webster's Revised Unabridged Dictionary
L., a felt cap
Chambers's Twentieth Century Dictionary
L. pileatuspileus, a cap of felt.


In literature:

Did he wear the cap of liberty, the pileus, at his master's funeral?
"The Ink-Stain, Complete" by Rene Bazin
Associated Words: mycology, agaricin, pileus, gills, spore.
"Putnam's Word Book" by Louis A. Flemming
The fine hair-like appendages on the pileus should be bolder.
"Scientific American Supplement, No. 643, April 28, 1888" by Various
A mushroom consists of a stem and a cap, or pileus.
"Among the Mushrooms" by Ellen M. Dallas and Caroline A. Burgin
When mature, it has a soft, convex, moist, smooth pileus, with a solid, somewhat bulbous stem, tinted with lilac.
"The Field and Garden Vegetables of America" by Fearing Burr
The scales on the pileus are more or less flattened, rather thin, clearly separated from the pileus, and easily removed.
"Studies of American Fungi. Mushrooms, Edible, Poisonous, etc." by George Francis Atkinson
The stem is colored like the pileus, whitish at the base, both it and the pileus are very fragile.
"The Mushroom, Edible and Otherwise" by M. E. Hard
It has a cinnamon-coloured pileus, with yellowish flesh, and its odour and flavour is said to partake of the same spice.
"Fungi: Their Nature and Uses" by Mordecai Cubitt Cooke
SMELL strong, especially at centre of pileus.
"Mushrooms of America, Edible and Poisonous" by Anonymous
Hymenophore continuous with the stem, veil woven into a fugacious web, which adheres to the margin of the pileus.
"Student's Hand-book of Mushrooms of America, Edible and Poisonous" by Thomas Taylor

In news:

Pileus clouds are caused by a fast-growing thunderstorm that shoves air into the upper atmosphere through a layer of moisture creating a layer of ice crystals.