c. 1300, relacioun, "relationship, connection, correspondence;" late 14c. as "act of telling or relating in words," from Anglo-French relacioun, Old French relacion "report, connection" (14c.) and directly from Latin relationem (nominative relatio) "a bringing back, restoring; a report, proposition," from relatus (see relate).
The meaning "person related by blood or marriage" is attested from c. 1500. The phrase no relation "not in the same family," used in differentiating persons with the same surname, is attested by 1930.
word-forming element meaning "quality, condition; act, power, skill; office, position; relation between," Middle English -schipe, from Old English -sciepe, Anglian -scip "state, condition of being," from Proto-Germanic *-skepi- (cognates: Old Norse -skapr, Danish -skab, Old Frisian -skip, Dutch -schap, German -schaft), from *skap- "to create, ordain, appoint," from PIE root *(s)kep-, forming words meaning "to cut, scrape, hack" (see shape (v.)). It often forms abstracts to go with corresponding concretes (friend/friendship, etc.).