Dacus is a genus of tephritid or fruit flies in the family Tephritidae.
Dacus may also refer to:
Adjectival form of Latin Dacia, ancient kingdom in Central and South-Eastern Europe Adjectival form of Latin Dacia (Denmark), medieval Latin name for Denmark or the Nordic region in general Dacus, Latinised name of the mediaeval English Denys family, of Danish origin Dacus (surname)