tartness vs thorniness

tartness and thorniness both are nouns.

Word	Noun	Adjective	Verb	Adverb
tartness	Yes	No	No	No
thorniness	Yes	No	No	No

As nouns, tartness and thorniness are synonyms defined as:

Other synonyms of tartness include acerbity, acrimony, bitterness, jaundice.

tartness (noun)	thorniness (noun)
a sharp sour taste	the quality of being covered with prickly thorns or spines
a rough and bitter manner	a rough and bitter manner
the taste experience when vinegar or lemon juice is taken into the mouth	The property of being full of difficulties, complexities, or controversial points.