the GNU version of the Collaborative International Dictionary of English
n. A genus of minute flagellate Infusoria of which there are many species, both free and attached. See Illust. under monad.
The Century Dictionary and Cyclopedia
n. A monad; a monadiform infusorian.
n. [capitalized] The typical genus of Monadidæ. M. lens is an example.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. a singular metaphysical entity from which material properties are said to derive
Word Usage
"The proper signification of the word monas (as employed by Leibnitz) ought to relate to the simple, given immediately as simple substance (for example, in consciousness), and not as an element of the composite."