dorsal fin


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Related to dorsal fin: caudal fin

dorsal fin

[′dȯr·səl ′fin]
(vertebrate zoology)
A median longitudinal vertical fin on the dorsal aspect of a fish or other aquatic vertebrate.

dorsal fin

dorsal fin
An additional fin surface along the top of the fuselage just in front of the main fin. Dorsal fins help increase directional stability, especially at high air speeds and Mach numbers.
References in periodicals archive ?
Adjust the length of the stinger wire so that the hook lies just in back of the dorsal fin of the live bait.
Above, the dorsal fin of the |basking shark which the pair spotted off Flamborough
On the logo design, the dorsal fin is formed inside the letter "B" with transmitter waves "spouting" like jets of water from a whale's blowhole.
Not only are they elongated, they also have a prominent dorsal fin which gives it an unusual "serpent" appearance.
They have a long, pointed dorsal fin and another long fin on their underside.
The whale, which briefly revealed its dorsal fin and tail on the water surface off Hong Kong Island's southwest again Wednesday, has moved a bit closer to international waters from a day earlier.
Slip the hook under the dorsal fin, leaving a bit of slack line to maximize the min- | now's swimming action.
eC[pounds sterling]So we felt that to experiment with the dorsal fin might not bring us the sufficient performance benefit weeCOd require to make it worthwhile.
Blyth Valley Council's coastal warden, Arthur Cranson, said: "Although they are only four to six inches long, these small fish have a very painful poisonous spine in their dorsal fin.