micrometeoroid vs micrometeor

micrometeoroid and micrometeor both are nouns.

Word	Noun	Adjective	Verb	Adverb
micrometeoroid	Yes	No	No	No
micrometeor	Yes	No	No	No

As nouns, micrometeoroid and micrometeor are synonyms defined as:

micrometeoroid and micrometeor: a meteorite or meteoroid so small that it drifts down to earth without becoming intensely heated in the atmosphere

Other synonyms of micrometeoroid include micrometeorite.

micrometeoroid (noun)	micrometeor (noun)
a meteorite or meteoroid so small that it drifts down to earth without becoming intensely heated in the atmosphere	a meteorite or meteoroid so small that it drifts down to earth without becoming intensely heated in the atmosphere