Meaning

noun a person related by blood or marriage

noun an animal or plant that bears a relationship to another (as related by common descent or by membership in the same genus)

adjective estimated by comparison; not absolute or complete

originFrom Middle French relatif, from Late Latin relātīvus, from Latin relātus, perfect passive participle of referō (“to carry back, to ascribe”), from re- (“again”) + ferō (“to bear or carry”). By surface analysis, relate + -ive.

Etymology from Wiktionary, CC BY-SA 3.0