nykäys

Nykäys is a Finnish noun that denotes a sudden, sharp movement or pull. It can describe a quick jerk of a limb, a rope, or a lever. More broadly, it may refer to a brief interruption or jolt in an ongoing action, such as a car jolt when the road surface changes or a switch causing a momentary impulse. In physiology and medicine, nykäys can describe a brief, involuntary contraction or twitch of a muscle, sometimes translated as a fasciculation in other languages.

Etymology: The word derives from the verb nykäistä, meaning to yank or pull suddenly. The noun nykäys nominalizes that action.

Usage: Nykäys is common in everyday Finnish and emphasizes the abrupt character of the movement. Examples: “Hänen käsivartensa teki nykäyksen, kun köysi kiristyi.” and “Auto jarrutti äkisti, ja matkustajat tunsivat pienen nykäyksen.” The plural nykäykset is used for multiple instances.

See also: Related terms include nykäistä (to yank) and nykiminen (twitching or tremor), as well as other words describing jolts such as jysäys.