/mon"euh treem'/ , n.
any animal of the Monotremata, the most primitive order of mammals, characterized by certain birdlike and reptilian features, as hatching young from eggs, and having a single opening for the digestive, urinary, and genital organs, comprising only the duckbill and the echidnas of Australia and New Guinea.
[ 1825-35; monotrème monotrema, assumed sing. of Monotremata, neut. pl. of MONOTREMATUS MONOTREMATOUS ]