yellowfin
noun /ˈjeləʊfɪn/
  /ˈjeləʊfɪn/
(plural yellowfin or yellowfins)
 (also yellowfin tuna 
 [countable, uncountable] /ˌjeləʊfɪn ˈtjuːnə/
  /ˌjeləʊfɪn ˈtuːnə/
)- a type of tuna (= a large sea fish used for food) that has yellow fins on its back