height vs tallness

height and tallness both are nouns.

Word	Noun	Adjective	Verb	Adverb
height	Yes	No	No	No
tallness	Yes	No	No	No

As nouns, height and tallness are synonyms defined as:

height and tallness: the vertical dimension of extension; distance from the base of something to the top

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

Other hyponyms of height include shortness, stockiness.

height (noun)	tallness (noun)
the vertical dimension of extension; distance from the base of something to the top	the vertical dimension of extension; distance from the base of something to the top
(of a standing person) the distance from head to foot	the property of being taller than average stature
elevation especially above sea level or above the earth's surface
the highest level or degree attainable; the highest stage of development