(lat'ĕr-ăl ret-i-nak'yū-lŭm ōr'bit), a confluence of fibrous supporting structures composed of the lateral horn of the levator aponeurosis, the lateral canthal tendon, the inferior suspensory (Lockwood) ligament, and the check ligaments of the lateral rectus muscle. The lateral retinaculum inserts into the lateral orbital tubercle.