venae sclerales vs vena

venae sclerales and vena both are nouns.

Word	Noun	Adjective	Verb	Adverb
venae sclerales	Yes	No	No	No
vena	Yes	No	No	No

As nouns, vena is a hypernym of venae sclerales; that is, vena is a word with a broader meaning than venae sclerales:

venae sclerales: tributaries of the anterior ciliary veins that drain the sclera of the eye
vena: a blood vessel that carries blood from the capillaries toward the heart

Other hypernyms of venae sclerales include vein, venous blood vessel.

venae sclerales (noun)	vena (noun)
tributaries of the anterior ciliary veins that drain the sclera of the eye	a blood vessel that carries blood from the capillaries toward the heart