Entry 1 sense Webster, 1913 Platypus /plăt'-əp-o͝osˌ/ · Plat·y·pus · IPA /ˈplætɪˌpʊs/ 01 n. The duck mole. See under Duck. 1. The duck mole. See under Duck.(Zool.) See: Duck Syn. Duck Mole, duckbill, duck-bill platypus, duck-billed platypus.