tart vs tartness

tart and tartness both are nouns.

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

tart (noun)	tartness (noun)
a small open pie with a fruit filling	a sharp sour taste
a pastry cup with a filling of fruit or custard and no top crust	a rough and bitter manner
a woman who engages in sexual intercourse for money	the taste experience when vinegar or lemon juice is taken into the mouth

tart (adjective)	tartness (adjective)
tasting sour like a lemon
harsh