Meaning of MUSHROOM in English

I. mush ‧ room 1 S3 /ˈmʌʃruːm, -rʊm/ BrE AmE noun [countable]

[ Date: 1400-1500 ; Language: French ; Origin: mousseron , from Latin mussirio ]

one of several kinds of ↑ fungus with stems and round tops, some of which can be eaten ⇨ toadstool :

mushroom soup

⇨ ↑ magic mushroom

II. mushroom 2 BrE AmE verb [intransitive]

to grow and develop very quickly:

New housing developments mushroomed on the edge of town.

Longman Dictionary of Contemporary English.      Longman - Словарь современного английского языка.