1rare Mouldiness, mustiness; mould.
In form Mucor. A genus of fungi, originally (especially in Linnaean use) comprising diverse (chiefly mould-forming) fungi and slime moulds, but later restricted to some fifty usually saprophytic zygomycetes which produce abundant mycelium; (also mucor) a fungus of this genus.
Mucor is closely related to the genus Rhizopus, with which it has been conflated and confused in the past, but its members lack stolons and produce sporangiophores from all parts of the mycelium.
Mid 17th century; earliest use found in Thomas Blount (1618–1679), antiquary and lexicographer. From classical Latin mūcor mustiness, mould from mūcēre to be mouldy (from mūcus) + -or.