terminal velocity vs velocity

terminal velocity and velocity both are nouns.

Word	Noun	Adjective	Verb	Adverb
terminal velocity	Yes	No	No	No
velocity	Yes	No	No	No

As nouns, velocity is a hypernym of terminal velocity; that is, velocity is a word with a broader meaning than terminal velocity:

terminal velocity: the constant maximum velocity reached by a body falling through the atmosphere under the attraction of gravity
velocity: distance travelled per unit time

Other hypernyms of terminal velocity include speed.

terminal velocity (noun)	velocity (noun)
the constant maximum velocity reached by a body falling through the atmosphere under the attraction of gravity	distance travelled per unit time