monad vs microorganism

monad and microorganism both are nouns.

Word	Noun	Adjective	Verb	Adverb
monad	Yes	No	No	No
microorganism	Yes	No	No	No

As nouns, microorganism is a hypernym of monad; that is, microorganism is a word with a broader meaning than monad:

monad: (biology) a single-celled microorganism (especially a flagellate protozoan)
microorganism: any organism of microscopic size

Other hypernyms of monad include micro-organism.

monad (noun)	microorganism (noun)
(biology) a single-celled microorganism (especially a flagellate protozoan)	any organism of microscopic size
a singular metaphysical entity from which material properties are said to derive
(chemistry) an atom having a valence of one