a. (Anat.) A term applied to a lachrymal gland on the inner side of the orbit of many animals which have a third eyelid, or nictitating membrane. See Nictitating membrane, under Nictitate. [ 1913 Webster ]
(n) Roman Emperor who was the adoptive son of Trajan; travelled throughout his empire to strengthen its frontiers and encourage learning and architecture; on a visit to Britain in 122 he ordered the construction of Hadrian's Wall (76-138), Syn. Publius Aelius Hadrianus, Adrian