anal fin

American  

noun

1. the median, unpaired fin on the ventral margin between the anus and the caudal fin in fishes.

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anal fin British  

noun

1. a median ventral unpaired fin, situated between the anus and the tail fin in fishes, that helps to maintain stable equilibrium

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Example Sentences

Hook the head section of the mullet through both lips, and the tail portion just above the anal fin.

From Time Magazine Archive

For better distance, hook the bait through the anal fin and either let the bait settle at the bottom or flow in the current.

From Time Magazine Archive

I drew a dorsal fin on top and an anal fin on the bottom, to prevent the shark from rolling side to side when it was moving forward.

From "The Line Tender" by Kate Allen

The latter are easily known by the test of the anal fin and tail.

From Fishing in British Columbia With a Chapter on Tuna Fishing at Santa Catalina by Lambert, Thomas Wilson

The anus, situated a short way before the anal fin, has a very small aperture.

From Discoveries in Australia, Volume 1. With an Account of the Coasts and Rivers Explored and Surveyed During The Voyage of H.M.S. Beagle, in the Years 1837-38-39-40-41-42-43. By Command of the Lords Commissioners of the Admiralty. Also a Narrative Of Captain Owen Stanley's Visits to the Islands in the Arafura Sea. by Stokes, John Lort