reddish brown vs Venetian red

reddish brown and Venetian red both are nouns.

Word	Noun	Adjective	Verb	Adverb
reddish brown	Yes	No	No	No
Venetian red	Yes	No	No	No

As nouns, reddish brown and Venetian red are synonyms defined as:

Other synonyms of reddish brown include burnt sienna, mahogany, sepia.

reddish brown (noun)	Venetian red (noun)
a shade of brown with a tinge of red	a shade of brown with a tinge of red