Word usually written using kana alone

Om; Aun; syllable representing the primordial trinity of Vishnu, Shiva and Brahma

inspiration and expiration; respiration; alpha and omega

Idiomatic expression

the harmonizing, mentally and physically, of two parties engaged in an activity; singing from the same hymn-sheet; dancing to the same beat

Buddhism

closed-mouthed form (statue with closed mouth, symbolizing the "um" half of "aum")

Buddhism

a-bi-ra-un-ken (mantra directed to Vairocana)