Definitions

from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun Botany The umbrellalike fruiting structure forming the top of a stalked fleshy fungus, such as a mushroom; the cap.
  • noun A brimless round skullcap worn by ancient Romans.

from The Century Dictionary.

  • noun A nipple-shield.
  • noun The disk or umbrella of a jellyfish.
  • noun Among the ancient Romans, a conical cap or hat of felt; a cap or skullcap.
  • noun 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.
  • noun In ornithology, same as pileum.
  • noun [capitalized] [NL.] A genus of echinoderms.

from the GNU version of the Collaborative International Dictionary of English.

  • noun (Rom. Antiq.) A kind of skull cap of felt.
  • noun (Bot.) The expanded upper portion of many of the fungi. See Mushroom.
  • noun (Zoöl.) The top of the head of a bird, from the bill to the nape.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun the cap of a mushroom.
  • noun the bell of a jellyfish
  • noun meteorology a small thin cloud attached to a cumulus cloud. A cap cloud
  • noun a conical felt hat worn in ancient Rome and Greece
  • noun The top of the head of a bird, from the bill to the nape.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun a fruiting structure resembling an umbrella or a cone that forms the top of a stalked fleshy fungus such as a mushroom

Etymologies

from The American Heritage® Dictionary of the English Language, 4th Edition

[New Latin pīleus, from Latin, cap.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

Latin pileus ("a felt cap").

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Examples

Comments

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  • Also pilleus or pilleum. A brimless felt cap somewhat similar to a fez. The pilleolus was a smaller cap, similar to a skullcap, especially associated with the manumission of slaves, who wore it upon their liberation. The pileus became popular in the 18th and 19th centuries, when became known as a liberty cap or Phrygian cap.

    August 15, 2008

  • A small horizontal cloud that can appear above a cumulus or cumulonimbus cloud, giving the other cloud a hood-like appearance.

    August 27, 2008

  • So it's a cloud with a hat? ;-)

    August 28, 2008

  • It's a dapper cloud.

    August 29, 2008