Skip-jack is a term commonly used to refer to small, agile, and fast-moving fish that live in both saltwater and freshwater environments. These fish are known for their distinctive dorsal fin, which is located far back on their bodies. While skip-jack is the most commonly used term to refer to these fish, there are several other synonyms that can be used, depending on the region and the species. Some of the most common synonyms include bonito, mackerel, tuna, and kahawai. Each of these terms refers to a specific type of skip-jack, with unique physical characteristics and behavioral patterns that distinguish them from one another.