The diverse order Carnivora ( or sometimes /ˌkɑrnɪˈvɔərə/; from Latin carō (stem carn-) "flesh", + vorāre "to devour") includes over 260 species of placental mammals. Its members are called carnivorans, while the word "carnivore" can refer to any meat-eating animal. Carnivorans are the most diverse in size of any mammalian order, ranging from the Least Weasel (Mustela nivalis), at as little as 25 grams and 11 cm (4.3 in), to the Polar bear (Ursus maritimus) which can weigh up to 1000 kg (2200 lb), to the Southern Elephant Seal whose adult males average 2,270 kg (5,000 lb) and measure 4.2 m (13.9 ft) (and may grow considerably larger).

The first carnivoran was a carnivore, and nearly all carnivorans today primarily eat meat. Some, such as cats, pinnipeds, and weasels, are almost completely carnivorous. Others, such as bears, are more omnivorous, although the Polar bear is predominantly carnivorous, with 90% of its diet consisting of seals. The Giant Panda is almost exclusively an herbivore but occasionally eats fish, eggs and insects.

Carnivorans have teeth and claws adapted for catching and eating other animals. Their eyes point forward. Many carnivorans hunt in packs and are social.

Carnivorans apparently evolved in North America out of members of the family Miacidae (miacids) c 42 million years ago. They soon split into catlike and doglike forms (feliformia and caniformia).