eyrie: [16] Latin ager (source of English agriculture and related to English acre) meant ‘field’, or more broadly ‘piece of land’. In postclassical times this extended via ‘native land’ to ‘lair of a wild animal, particularly a bird of prey’, the meaning of its Old French descendant aire. The Old French form was taken back into medieval Latin as aeria, the immediate source of the English word. => acre, agriculture