Venetian red vs burnt sienna

Venetian red and burnt sienna both are nouns.

Word	Noun	Adjective	Verb	Adverb
Venetian red	Yes	No	No	No
burnt sienna	Yes	No	No	No

As nouns, Venetian red and burnt sienna are synonyms defined as:

Other synonyms of Venetian red include mahogany, reddish brown, sepia.

Venetian red (noun)	burnt sienna (noun)
a shade of brown with a tinge of red	a shade of brown with a tinge of red
	a reddish-brown pigment produced by roasting sienna