ENGLISH
REFERENCE

mushroom

n. · adj.
US //ˈməʃɹum// UK //mˈʌʃɹuːm// mush·room
  1. 1 fungus/food (n.)
    A1 Beginner

    a fungus with a stem and a round top, often grown for food.

    the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground on soil or a food source.

    Example

    I added some sliced mushrooms to the pasta sauce for extra flavour.

    Example

    The chef foraged for wild mushrooms in the forest, carefully avoiding the toxic varieties that closely resemble edible species.
  2. 2 something that grows fast (n.)
    B2 Upper Intermediate

    something that appears or grows very suddenly.

    an object or entity that appears or develops with remarkable speed, often used figuratively.

    Example

    New apartment buildings appeared like mushrooms all over the city.

    Example

    The sudden appearance of these tech startups, growing like mushrooms in the industrial district, transformed the local economy within a single decade.
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  1. 3 architecture (n.)
    C2 Proficiency Technical Science

    a strong concrete post with a wide top used to hold up a ceiling.

    a reinforced concrete column with a flared head, designed to support a flat slab without the need for beams.

    Example

    The garage used mushroom columns to support the heavy concrete floor above.

    Example

    The architect specified mushroom construction for the warehouse to maximise vertical clearance and ensure even load distribution across the floor slabs.
  2. 4 shaped like a mushroom (adj.)
    B2 Upper Intermediate

    having the shape or look of a mushroom.

    resembling a mushroom in form, particularly having a narrow base and a broad, rounded top.

    Example

    The explosion created a huge mushroom cloud in the sky.

    Example

    The designer chose a mushroom lamp for the bedside table, citing its soft curves and mid-century aesthetic.
    • bulbous
Origin

From Middle English muscheron, musseron, from Anglo-Norman musherum, moscheron, from Old French moisseron, of obscure origin: probably derived from Old French mosse, moise ("moss"; whence also French mousse), as the use first applied to a type of fungus which grows in moss, from Frankish mosu (“moss”) or Old Dutch mosa (“moss”), akin to Old High German mosa (“moor, swamp”), Old High German mos (“moss, bog”), Old High German mios (“moss, mire”), Old English mēos (“moss”), Old English mōs (“bog, marsh”), Old Norse mosi (“moss”), Old Norse myrr (“bog, mire”), from Proto-Germanic musą, musô, miuziz (“mosses, bog”), from Proto-Indo-European mews- (“mosses, mold, mildew”). Displaced native Old English swamm. More at mire. Alternatively, the Old French may be of pre-Roman origin. See Ancient Greek μύκης (múkēs, “mushroom”). Doublet of moss and mousse.

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