coequal |kōˈēkwəl|
adjective
equal with one another; having the same rank or importance : coequal partners.
noun
a person or thing equal with another.
DERIVATIVES
coequality |ˌkō-iˈkwälitē| noun
ORIGIN late Middle English : from Latin coaequalis ‘of the same age,’ from co- ‘jointly’ + aequalis (see equal ).Somehow it does not seem to be redundantly redundant.
Thank you. It reinforces that "co" is different in meaning from "equal" or either would suffice for the same meaning.