Wiktionary
cygnine
Etymology 1 a. 1 (context zoology English) Being of the genus ''Cygnus'' (swan), within subfamily Anserinae of the family Anatidae, though sometimes considered a distinct subfamily, ''(taxlink Cygninae subfamily noshow=1)''. 2 Of, concerning, pertaining to, resembling, or having the characteristics of a swan or swans. Etymology 2
n. (context dated English) An alkaloid from plants of genus (taxlink Gastrolobium genus noshow=1), found in Australia, principally Western Australia, highly toxic to introduced animals.