carrier pigeon(n = noun.animal) - a homing pigeon used to carry messages;
is a kind of homer, homing pigeon

N  carrier, porter, bearer, tranter, conveyer, cargador, express, expressman, stevedore, coolie, conductor, locomotive, motor, beast, beast of burden, cattle, horse, nag, palfrey, Arab, blood horse, thoroughbred, galloway, charger, courser, racer, hunter, jument, pony, filly, colt, foal, barb, roan, jade, hack, bidet, pad, cob, tit, punch, roadster, goer, racehorse, pack horse, draft horse, cart horse, dray horse, post horse, ketch, Shetland pony, shelty, sheltie, garran, garron, jennet, genet, bayard, mare, stallion, gelding, bronco, broncho, cayuse, creature, critter, cow pony, mustang, Narraganset, waler, stud, Pegasus, Bucephalus, Rocinante, ass, donkey, jackass, mule, hinny, sumpter horse, sumpter mule, burro, cuddy, ladino, reindeer, camel, dromedary, llama, elephant, carrier pigeon, pallet, brace, cart, dolley, support, fork lift, carriage, ship, equine, asinine.

N  messenger, envoy, emissary, legate, nuncio, internuncio, ambassador, marshal, flag bearer, herald, crier, trumpeter, bellman, pursuivant, parlementaire, apparitor, courier, runner, dak, estafette, Mercury, Iris, Ariel, commissionaire, errand boy, chore boy, newsboy, mail, overnight mail, express mail, next-day delivery, post, post office, letter bag, delivery service, United Parcel Service, UPS, Federal Express, Fedex, telegraph, telephone, cable, wire (electronic information transmission), carrier pigeon, (news) 532 reporter, gentleman of the press, representative of the press, penny-a-liner, special correspondent, own correspondent, spy, scout, informer.

aircraft carrier, armored personnel carrier, armoured personnel carrier, attack aircraft carrier, ball carrier, band-tail pigeon, band-tailed pigeon, car carrier, card carrier, carrier, carrier bag, carrier electrophoresis, carrier wave, clay pigeon, common carrier, domestic pigeon, hod carrier, homing pigeon, immune carrier, letter carrier, luggage carrier, mail carrier, passenger pigeon, personnel carrier, pigeon, pigeon berry, pigeon breast, pigeon droppings, pigeon guillemot, pigeon hawk, pigeon loft, pigeon pea, pigeon toed, pigeon toes, pouter pigeon, rock pigeon, sea pigeon, spear carrier, stool pigeon, troop carrier, tumbler pigeon, water carrier, weapons carrier, wood pigeon