guan Syllabification: (guan)Pronunciation: /gwän/Definition of guan noun a large, pheasantlike, tree-dwelling bird of tropical American rain forests. Family Cracidae (the guan family): several genera, especially Penelope. The guan family also includes curassows and chachalacas Origin: late 17th century: via American Spanish from Miskito kwamuguan in other Oxford dictionaries Definition of guan in the British & World English dictionary