articulateness vs fluency

articulateness and fluency both are nouns.

Word	Noun	Adjective	Verb	Adverb
articulateness	Yes	No	No	No
fluency	Yes	No	No	No

As nouns, articulateness and fluency are synonyms defined as:

articulateness and fluency: the quality of being facile in speech and writing

Other synonyms of articulateness include volubility.

articulateness (noun)	fluency (noun)
the quality of being facile in speech and writing	the quality of being facile in speech and writing
	skillfulness in speaking or writing
	powerful and effective language