Substantiate is a related term of ratify.

In lang=en terms the difference between substantiate and ratify

is that substantiate is to give material form or substance to something; to embody; to record in documents while ratify is to give formal consent to; make officially valid.

As verbs the difference between substantiate and ratify

is that substantiate is to verify something by supplying evidence; to authenticate or corroborate while ratify is to give formal consent to; make officially valid.