from
The Collaborative International Dictionary of English v.0.48
Monad \Mon"ad\, n. [L. monas, -adis, a unit, Gr. ?, ?, fr.
mo`nos alone.]
1. An ultimate atom, or simple, unextended point; something
ultimate and indivisible.
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2. (Philos. of Leibnitz) The elementary and indestructible
units which were conceived of as endowed with the power to
produce all the changes they undergo, and thus determine
all physical and spiritual phenomena.
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3. (Zool.) One of the smallest flagellate Infusoria; esp.,
the species of the genus {Monas}, and allied genera.
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4. (Biol.) A simple, minute organism; a primary cell, germ,
or plastid.
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5. (Chem.) An atom or radical whose valence is one, or which
can combine with, be replaced by, or exchanged for, one
atom of hydrogen.
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{Monad deme} (Biol.), in tectology, a unit of the first order
of individuality.
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