Definition of sailfish
noun (plural same or sailfishes)
- a fish with a high sail-like dorsal fin, in particular:
- an edible migratory billfish that is a prized game fish (genus Istiophorus, family Istiophoridae, in particular I. platypterus). (also Celebes sailfish) a small tropical freshwater fish of Sulawesi, popular in aquaria (Telmatherina ladigesi, family Atherinidae).