An unpaired fin located on the underside of a fish posterior to the anus.
More example sentences
- The second dorsal and the anal fin are well-separated from the caudal fin.
- The fleshy, stalk-like pectoral and pelvic fins and similar fleshy second dorsal and anal fins are also unlike any other marine fishes.
- Dorsal and anal fins are typically completely formed by the time the fish has reached 7-13 mm.
Definition of anal fin in:
- The British & World English dictionary