Definition of fin in English:

fin

Syllabification: fin

noun

  • 1A flattened appendage on various parts of the body of many aquatic vertebrates and some invertebrates, including fish and cetaceans, used for propelling, steering, and balancing.
    More example sentences
    • He then uses this to explain why there are no post-anal fins in fish: the tail is itself an appendage.
    • Powerful fins propel the streamlined fish toward meals of smaller fish and squid - and away from hungry sharks.
    • In essence, only the paired fins and the tail fin remain.
  • 1.1An underwater swimmer’s flipper.
    More example sentences
    • Training equipment such as kickboards, pull buoys, and fins help all swimmers to isolate or emphasize certain movements.
    • The next steps involve the whole stroke, removing the fins, underwater kicking to stroke start and finally the block start.
    • You take a look around the pool and are surprised to see that a number of swimmers are using fins, especially on kick sets.
  • 1.2A small flattened projecting surface or attachment on an aircraft, rocket, or automobile, providing aerodynamic stability or serving as a design element.
    More example sentences
    • The center fin was a fixed surface, extending vertically above the stabilizer at the center line of the airplane.
    • Simply described, the fins improve directional stability by channeling and smoothing the airflow around the tailcone.
    • Aerodynamic fins located on the aft bay of the strap-ons also provided for flight control.
  • 1.3A flattened projection on a device, such as a radiator, used for increasing heat transfer.
    More example sentences
    • The fins conduct heat from the tubes and then transfer it to the air flowing through the radiator.
    • Concrete structural fins act as shading devices on the north-south axis.
    • The top and bottom of the Cool Drive have fins for heat dissipation.

verb (fins, finning, finned)

[no object] Back to top  
  • Swim underwater by means of flippers: I finned madly for the surface
    More example sentences
    • They then did some shallow water running followed by duck diving and finning (swimming with flippers).
    • I finned along the starboard side to the base of the bow, where I found a monster edible crab.
    • We finned back along the port side and, after a bottom time of 15 minutes, our slow ascent up the shotline commenced.

Derivatives

finless

adjective
More example sentences
  • Researchers in inspection stations will closely watch the white-flag dolphins and finless porpoises.
  • These butchered, finless, and fully conscious creatures, sink to the bottom.
  • Below the iconic duo a trio of very sorry looking, finless, sharks are shown floundering.

finned

adjective
[in combination]: primitive ray-finned fishes

Origin

Old English finn, fin, of Germanic origin; related to Dutch vin and probably ultimately to Latin pinna 'feather, wing'.

More definitions of fin

Definition of fin in:

Get more from Oxford Dictionaries

Subscribe to remove ads and access premium resources

Word of the day astrogation
Pronunciation: ˌastrəˈgāSHən
noun
(in science fiction) navigation in outer space