moss

verb

mossed; mossing; mosses

transitive verb

: to cover or overgrow with moss

Word History

First Known Use

15th century, in the meaning defined above

Time Traveler
The first known use of moss was in the 15th century

Cite this Entry

“Moss.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/moss. Accessed 9 Jun. 2026.

Kids Definition

moss

noun
ˈmȯs
1
: any of a class of plants that have no flowers and produce small leafy stems forming sex organs at their tips and that grow in patches like cushions on rocks, bark, or damp ground
2
: any of various plants (as lichens) resembling mosses compare reindeer moss
mosslike
-ˌlīk
adjective
mossy
ˈmȯ-sē
adjective

Medical Definition

moss

noun
1
: any of a division (Bryophyta) of plants having a small leafy often tufted stem bearing sex organs at its tip see sphagnum
2
: any of various plants resembling mosses in appearance or habit of growth see club moss, iceland moss, irish moss

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