barn vs square measure

barn and square measure both are nouns.

Word	Noun	Adjective	Verb	Adverb
barn	Yes	No	No	No
square measure	Yes	No	No	No

As nouns, square measure is a hypernym of barn; that is, square measure is a word with a broader meaning than barn:

barn: (physics) a unit of nuclear cross section; the effective circular area that one particle presents to another as a target for an encounter
square measure: a system of units used to measure areas

Other hypernyms of barn include area unit.

barn (noun)	square measure (noun)
an outlying farm building for storing grain or animal feed and housing farm animals	a system of units used to measure areas
(physics) a unit of nuclear cross section; the effective circular area that one particle presents to another as a target for an encounter