fin

Definitions

General English

General Science

  • noun a thin flat projection on the body of a fish
  • noun a fixed vertical aerofoil at the rear of an aircraft

Aviation

Cars & Driving

  • noun a projecting thin flat part, such as the cooling fins on an air-cooled cylinder, or the large vertical member at the rear of some streamlined record-breaking cars, intended to aid directional stability

Construction

  • A narrow, linear projection on a formed concrete surface, resulting from mortar flowing out between spaces in the formwork.

Electronics

  • A projecting plate or vane utilized for cooling a component, device, or piece of equipment. It provides an additional surface area for the dissipation of heat. Also called cooling fin.

Military

  • noun a thin, flat projection on an aircraft, missile or other projectile, which provides extra stability during flight

Slang

  • noun a five-dollar bill. From the Yiddish finif, meaning five.

Origin & History of “fin”

Fin is a word common to the Germanic languages of northeast Europe (German has finne, Dutch vin), but its ultimate source is not clear. The likeliest candidate is Latin pinna ‘feather, wing’ (source of English pin, pinion, and pinnacle), although another suggestion is Latin spīna ‘thorn, spike’.
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