- a unit; something simple and indivisible
- any simple, single-celled organism, specif., a simple type of flagellated protozoan or protist
- any of the four nuclei formed at the completion of meiosis
- Chem. a monovalent atom, element, or radical
- Philos. an entity or elementary being thought of as a microcosm or ultimate unit
Origin: LL monas (gen. monadis) from Glassical Greek monas (gen. monados), a unit, unity from monos, alone: see mono-
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- Philosophy An indivisible, impenetrable unit of substance viewed as the basic constituent element of physical reality in the metaphysics of Leibniz.
- Biology A single-celled microorganism, especially a flagellate protozoan of the genus Monas.
- Chemistry An atom or a radical with valence 1.
Origin: Latin monas, monad-, unit, from Greek, from monos, single; see men-4 in Indo-European roots.
- mo·nadˈic , mo·nadˈi·cal adjective
- mo·nadˈi·cal·ly adverb
- moˈnad·ism noun
monad - Medical Definition
- An atom or a radical with a valence of 1.
- A single-celled microorganism, especially a protozoan of the genus Monas.
- Any of the four chromatids of a tetrad that, after the first and second meiotic divisions, separate to become the chromosomal material in each of the four daughter cells.
- monadic , mo·nadˈi·cal adjective