Having long fins, as a fish, or flippers, as the finner whale.
The Century Dictionary (Public Domain)
Use "long-finned" in a sentence
"Furthermore, the International Union for Conservation of Nature IUCN states that the species is "data deficient" and the actual number of long-finned pilot whales that exist in the ocean today is unknown."
"The IUCN estimate is that there are approximately 200,000 short-finned pilot whales, and that the number of long-finned pilot whales are much less."
"Other species of small whales and dolphins present are the dusky dolphin Lagenorhynchus obscurus (DD), Peale's dolphin L. australis (DD), Commerson's dolphin Cephalorhynchus commersonii (DD) and long-finned pilot whale Globycephala melas."