thirstiness vs aridity

thirstiness and aridity both are nouns.

Word	Noun	Adjective	Verb	Adverb
thirstiness	Yes	No	No	No
aridity	Yes	No	No	No

As nouns, thirstiness and aridity are synonyms defined as:

thirstiness and aridity: a deficiency of moisture (especially when resulting from a permanent absence of rainfall)

Other synonyms of thirstiness include aridness.

thirstiness (noun)	aridity (noun)
strong desire for something (not food or drink)	the quality of yielding nothing of value
a physiological need to drink	a deficiency of moisture (especially when resulting from a permanent absence of rainfall)
a deficiency of moisture (especially when resulting from a permanent absence of rainfall)