truth vs exactitude

truth and exactitude both are nouns.

Word	Noun	Adjective	Verb	Adverb
truth	Yes	No	No	No
exactitude	Yes	No	No	No

As nouns, exactitude is a hyponym of truth; that is, exactitude is a word with a more specific, narrower meaning than truth:

Other hyponyms of truth include exactness, fidelity.

truth (noun)	exactitude (noun)
the quality of being near to the true value	the quality of being exact
a fact that has been verified
a true statement
conformity to reality or actuality