sub-rosa vs behind-the-scenes

sub-rosa and behind-the-scenes both are adjectives.

Word	Noun	Adjective	Verb	Adverb
sub-rosa	No	Yes	No	No
behind-the-scenes	No	Yes	No	No

As adjectives, sub-rosa and behind-the-scenes are synonyms defined as:

sub-rosa and behind-the-scenes: designed and carried out secretly or confidentially

Other synonyms of sub-rosa include under-the-table.

sub-rosa (adjective)	behind-the-scenes (adjective)
designed and carried out secretly or confidentially	designed and carried out secretly or confidentially