noun \ˈms\

: a type of green plant that has very small leaves and no flowers and that grows on rocks, bark, or wet ground

Full Definition of MOSS

chiefly Scottish :  bog, swamp; especially :  a peat bog
a :  any of a class (Musci) of bryophytic plants characterized by a gametophyte having a small leafy often tufted stem bearing sex organs at its tip; also :  a clump or sward of these plants
b :  any of various plants resembling moss in appearance or habit of growth
:  a mossy covering
moss·like \-ˌlīk\ adjective

Examples of MOSS

  1. Moss covered the fallen logs.

Origin of MOSS

Middle English, from Old English mos; akin to Old High German mos moss, Latin muscus
First Known Use: before 12th century

Rhymes with MOSS



Definition of MOSS

transitive verb
:  to cover or overgrow with moss

First Known Use of MOSS

15th century


noun \ˈms\   (Medical Dictionary)

Medical Definition of MOSS

: any of a class (Musci) of bryophytic plants having a small leafy often tufted stem bearing sex organs at its tip—see sphagnum
: any of various plants resembling mosses in appearance or habit of growth—see club moss, iceland moss, irish moss


noun    (Concise Encyclopedia)

Any of at least 12,000 species of small, spore-bearing land plants in the bryophyte division, found worldwide except in salt water. Mosses are simple and ancient plants that have survived nearly unchanged since the Permian Period (290–248 million years ago). Commonly found in moist, shady locations (e.g., forest floors), mosses may range in size from microscopic to more than 40 in. (1 m) long. They prevent erosion and release nutrients from the substrates on which they grow. The life cycle shows clear alternation of generations between the sexual gametophyte, with stemlike and leaflike structures that produce eggs and swimming sperm, and the sporophyte, a raised stalk that ends in a spore case (sporangium). Mosses also reproduce asexually by branching. The economically important genus Sphagnum forms peat. Many so-called mosses are not bryophytes, including Irish moss (a red form of algae); beard moss, Iceland moss, oak moss, and reindeer moss (all lichens); Spanish moss (a name used variously for a lichen or an air plant of the pineapple family); and club moss (an evergreen herb of the family Lycopodiaceae).


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