steradian vs angular unit

steradian and angular unit both are nouns.

Word	Noun	Adjective	Verb	Adverb
steradian	Yes	No	No	No
angular unit	Yes	No	No	No

As nouns, angular unit is a hypernym of steradian; that is, angular unit is a word with a broader meaning than steradian:

steradian: the unit of solid angle adopted under the Systeme International d'Unites
angular unit: a unit of measurement for angles

steradian (noun)	angular unit (noun)
the unit of solid angle adopted under the Systeme International d'Unites	a unit of measurement for angles