Dactylis glomerata vs orchard grass

Dactylis glomerata and orchard grass both are nouns.

Word	Noun	Adjective	Verb	Adverb
Dactylis glomerata	Yes	No	No	No
orchard grass	Yes	No	No	No

As nouns, Dactylis glomerata and orchard grass are synonyms defined as:

Dactylis glomerata and orchard grass: widely grown stout Old World hay and pasture grass

Other synonyms of Dactylis glomerata include cocksfoot, cockspur.

Dactylis glomerata (noun)	orchard grass (noun)
widely grown stout Old World hay and pasture grass	widely grown stout Old World hay and pasture grass