A major division of the rodents that includes the guinea pigs, porcupines, coypu, and their relatives. They occur chiefly in South America.→ rodent
- ‘The Guinea Pig, Cavia porcellus, is a mammal of the order Rodentia, sub-order Hystricomorpha and family Caviidae.’
- ‘The Old World members of this group are sometimes placed in a separate group called the porcupine-like rodents (Hystricomorpha).’
Modern Latin (plural), from Latin hystrix, hystric- porcupine (from Greek hustrix) + morphē form.