Late 19th century; earliest use found in Transactions of the Asiatic Society of Japan. From Japanese omi clan chieftain (720 in Nihon-shoki, the Chronicles of Japan), fused compound of uncertain origin. Probably a contraction of ō-mi (from ō- great) + mi- revered being, god, but frequently apprehended as from ō- + mi body, person.
Originally among German communities: a grandmother.
1980s. From German Omi from Om- (in Oma) + -i, hypocoristic suffix.
Oblate Fathers of Mary Immaculate.
Early 20th century; earliest use found in The Catholic Encyclopaedia.