(Japanese mythology) A tortoise-like demon or imp.

The tenth letter of the Greek alphabet. / (finance) A measurement of the sensitivity of the value of an option to changes in the implied volatility of the price of the underlying asset.

plural of kappa

(Twitch-speak) An emote, often used as a postscript, to indicate that the preceding statement is sarcastic or false.

(Internet) Used to indicate sarcasm in imitation of Kappa as used on Twitch.tv

plural of Fleiss' kappa

(statistics) A statistical measure for assessing the reliability of agreement between a fixed number of raters.

(UK, slang, derogatory) A female chav or townie.

plural of Kappa slapper

A temporal perceptual illusion that can arise when observers judge the elapsed time between sensory stimuli applied sequentially at different locations. Subjects tend to overestimate the time between stimuli when the distance between the stimuli is large, and to underestimate the time when the distance is small.