red lead vs minium

red lead and minium both are nouns.

Word	Noun	Adjective	Verb	Adverb
red lead	Yes	No	No	No
minium	Yes	No	No	No

As nouns, red lead and minium are synonyms defined as:

red lead and minium: a reddish oxide of lead (Pb3O4) used as a pigment in paints and in glass and ceramics

red lead (noun)	minium (noun)
a reddish oxide of lead (Pb3O4) used as a pigment in paints and in glass and ceramics	a reddish oxide of lead (Pb3O4) used as a pigment in paints and in glass and ceramics