The Collaborative International Dictionary of English v.0.48:

Carnivore \Car`ni*vore\, n. [Cf. F. carnivore.] (Zool.)
   One of the Carnivora.
   [1913 Webster]

WordNet (r) 3.0 (2006):

carnivore
    n 1: a terrestrial or aquatic flesh-eating mammal; "terrestrial
         carnivores have four or five clawed digits on each limb"
    2: any animal that feeds on flesh; "Tyrannosaurus Rex was a
       large carnivore"; "insectivorous plants are considered
       carnivores"

Moby Thesaurus II by Grady Ward, 1.0:

67 Moby Thesaurus words for "carnivore":
   Brillat-Savarin, Chiroptera, Lagomorpha, Lucullus, Primates,
   Rodentia, amphibian, aquatic, biped, board-and-roomer, boarder,
   bon vivant, canine, cannibal, connoisseur of food, consumer,
   cosmopolite, diner, diner-out, eater, eater-out, epicure, feeder,
   feline, flesh-eater, fruitarian, gastronome, glutton, gnawer,
   gourmand, gourmet, grain-eater, graminivore, granivore, herbivore,
   high liver, hungry mouth, insectivore, invertebrate,
   lactovegetarian, luncher, mammal, mammalian, man-eater, marsupial,
   marsupialian, meat-eater, mouth, omnivore, omophagist,
   pantophagist, phytophage, picnicker, plant-eater, predacean,
   primate, quadruped, reptile, rodent, ruminant, scavenger,
   trencherman, ungulate, varmint, vegetarian, vermin, vertebrate