noun: (Hinduism, Buddhism) A sacred, mystical syllable used in prayer and meditation.
verb: (intransitive) To chant the sacred syllable om.
noun: (politics) Initialism of Occupy movement.
noun: (Commonwealth, UK) Initialism of Order of Merit. (a dynastic order of the Royal House of Windsor)
noun: (aviation) Initialism of outer marker. [(aviation) A type of marker beacon placed to indicate the final approach fix of an ILS or IGS approach, triggering a continuous sequence of visual and aural Morse code dashes from the marker beacon receiver in the cockpit of an aircraft flying over the marker.]
noun: (medicine) Initialism of otitis media. [(pathology) An inflammation of the middle ear.]
noun: Initialism of old measurement.
noun: (CB radio slang) Initialism of old man (term of address for a male). [An elderly man.]