subluxation UK /ˌsʌb.lʌkˈseɪ.ʃən/US /ˌsəbˌləkˈseɪ.ʃən/ noun1 •A partial dislocation of a joint, in which the articulating surfaces remain in partial contact.The patient experienced subluxations of his right ulna, his lower right rear molar, and the lens of his left eye. formssubluxations