From WordNet (r) 3.0 (2006):
carrier
n 1: someone whose employment involves carrying something; "the
bonds were transmitted by carrier" [syn: carrier,
bearer, toter]
2: a self-propelled wheeled vehicle designed specifically to
carry something; "refrigerated carriers have revolutionized
the grocery business"
3: a large warship that carries planes and has a long flat deck
for takeoffs and landings [syn: aircraft carrier,
carrier, flattop, attack aircraft carrier]
4: an inactive substance that is a vehicle for a radioactive
tracer of the same substance and that assists in its recovery
after some chemical reaction
5: a person or firm in the business of transporting people or
goods or messages [syn: carrier, common carrier]
6: a radio wave that can be modulated in order to transmit a
signal [syn: carrier wave, carrier]
7: a man who delivers the mail [syn: mailman, postman, mail
carrier, letter carrier, carrier]
8: a boy who delivers newspapers [syn: carrier, newsboy]
9: (medicine) a person (or animal) who has some pathogen to
which he is immune but who can pass it on to others [syn:
carrier, immune carrier]
10: a rack attached to a vehicle; for carrying luggage or skis
or the like
11: (genetics) an organism that possesses a recessive gene whose
effect is masked by a dominant allele; the associated trait
is not apparent but can be passed on to offspring