monoatomic vs monatomic

monoatomic and monatomic both are adjectives.

Word	Noun	Adjective	Verb	Adverb
monoatomic	No	Yes	No	No
monatomic	No	Yes	No	No

As adjectives, monoatomic and monatomic are synonyms defined as:

monoatomic and monatomic: of or relating to an element consisting of a single atom

monoatomic (adjective)	monatomic (adjective)
of or relating to an element consisting of a single atom	of or relating to an element consisting of a single atom