noun \ˈməsh-ˌrüm, -ˌrm; chiefly Northern & Midland -ˌrün; dial ˈmə-shə-ˌrüm, -ˌrm, -ˌrün\

: a fungus that is shaped like an umbrella; especially : one that can be eaten

Full Definition of MUSHROOM

a :  an enlarged complex aboveground fleshy fruiting body of a fungus (as a basidiomycete) that consists typically of a stem bearing a pileus; especially :  one that is edible
b :  fungus
:  upstart
:  something resembling a mushroom

Examples of MUSHROOM

  1. cut up some mushrooms for the salad

Origin of MUSHROOM

Middle English musheron, from Anglo-French musherum, musseron, from Late Latin mussirion-, mussirio
First Known Use: 15th century



: to increase or develop very quickly

: to collect wild mushrooms

Full Definition of MUSHROOM

intransitive verb
a :  to well up and spread out laterally from a central source
b :  to become enlarged or extended :  grow
:  to collect wild mushrooms
:  to spring up suddenly or multiply rapidly

Examples of MUSHROOM

  1. Interest in local history is suddenly mushrooming.
  2. Her hobby mushroomed into a thriving business.
  3. He goes mushrooming in the spring every year.

First Known Use of MUSHROOM



noun \ˈməsh-ˌrüm, -ˌrm\   (Medical Dictionary)

Medical Definition of MUSHROOM

: an enlarged complex fleshy fruiting body of a fungus (as most basidiomycetes) that arises from an underground mycelium and consists typically of a stem bearing a spore-bearing structure; especially : one that is edible—compare toadstool
: fungus 1


noun    (Concise Encyclopedia)

A mushroom typically consists of a stalk (stipe) and a cap (pileus). As the mushroom develops from …—© Merriam-Webster Inc.

Fleshy spore-bearing structure of certain fungi (see fungus), typically of the phylum Basidiomycota. It arises from the mycelium, which may live hundreds of years or a few months, depending on its food supply. Some species grow cellular strands (hyphae) in all directions, forming a circular mat with a “fairy ring” of fruiting bodies around the outside. Popularly, “mushroom” refers to the edible sporophores, while “toadstool” refers to inedible or poisonous sporophores, but there is no scientific distinction between the two names. Umbrella-shaped sporophores with spore-shedding gills on the undersurface are found chiefly in the agaric family (Agaricaceae). Mushrooms that are cap-shaped and bear spores in an easily detachable layer on the underside of the cap belong to the family Boletaceae. Together the agarics and boletes include most of the forms known as mushrooms. The morels (phylum Ascomycota) are popularly included with the true mushrooms because of their shape and fleshy structure. Since some poisonous mushrooms closely resemble edible ones, mushrooms intended for eating must be accurately identified. Mushroom poisoning can cause nausea, diarrhea, vomiting, cramps, hallucinations, coma, and sometimes death.


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