/plat"i peuhs, -poos'/ , n. , pl. platypuses, platypi /-puy'/ .
a small, aquatic, egg-laying monotreme, Ornithorhynchus anatinus, of Australia and Tasmania, having webbed feet, a tail like that of a beaver, a sensitive bill resembling that of a duck, and, in adult males, venom-injecting spurs on the ankles of the hind limbs, used primarily for fighting with other males during the breeding season. Also called duckbill, duckbilled platypus .
[ 1790-1800; platýpous flat-footed, equiv. to platy- PLATY- + -pous, adj. deriv. of poús FOOT ]