orthodontic

adj of orthodontics 正牙（学）的: orthodontic surgery 正牙外科.

originality, originally, originate, originator, oriole, ormolu, ornament, ornamental, ornamentation, ornate, ornately, ornateness, ornithological, ornithologist, ornithology, orotund, orphan, orphanage, orris-root, orth(o)-, orthodontics, orthodontist, orthodox, orthodoxy, orthographic (also orthographical), orthographically, orthography, orthopaedic (also orthopedic), orthopaedics (also orthopedics), orthopaedist (also orthopedist), ortolan, oryx, OS, Oscar, oscillate, oscillation, oscillator, oscillograph, oscilloscope, osier,