pithiness vs concision

pithiness and concision both are nouns.

Word	Noun	Adjective	Verb	Adverb
pithiness	Yes	No	No	No
concision	Yes	No	No	No

As nouns, pithiness and concision are synonyms defined as:

pithiness and concision: terseness and economy in writing and speaking achieved by expressing a great deal in just a few words

Other synonyms of pithiness include conciseness, succinctness.

pithiness (noun)	concision (noun)
terseness and economy in writing and speaking achieved by expressing a great deal in just a few words	terseness and economy in writing and speaking achieved by expressing a great deal in just a few words