# kappa

/ˈkæpə/ (US) · /kˈæpɐ/ (UK)

Source: https://englishreference.com/word/kappa
Updated: 2026-08-08

## Senses

### 1. Greek letter

noun · CEFR B2 · Technical

the tenth letter of the Greek alphabet.

For teachers: the tenth letter of the Greek alphabet, represented as Κ or κ.

- The scientist used the Greek letter kappa to represent a specific constant in the equation.
- In fluid mechanics, the von Kármán constant is often represented by the Greek letter kappa to describe the logarithmic velocity profile of a turbulent flow.

### 2. Japanese folklore

noun · CEFR C1 · Literary

a legendary Japanese creature that lives in water and looks like a mix between a human and a turtle.

For teachers: a reptilian water sprite or yōkai from Japanese folklore, typically depicted as having a beak, a shell, and a water-filled cavity on its head.

- In the old story, the kappa would only leave people alone if they gave it a cucumber.
- The protagonist encountered a kappa by the riverbank, a creature known in local legend for its polite manners and mischievous nature.

### 3. internet sarcasm

noun · CEFR C2 · Slang · Informal

a word or image used at the end of a sentence to show that you are joking or being sarcastic.

For teachers: an emote or postscript used in digital communication to signal irony, sarcasm, or that the preceding statement was a joke.

- I definitely enjoy waking up at 4 a.m. for work, kappa.
- The streamer's chat was flooded with the kappa emote after he jokingly claimed to be the best player in the world despite losing the match.

Usage: Usually placed at the very end of a sentence or message.

Teaching tip: Originating from the streaming platform Twitch, this is highly specific to internet culture and may not be understood by older or non-digital audiences.

### 4. finance metric

noun · CEFR C2 · Technical

a way to measure how much the price of an option changes when market volatility changes.

For teachers: a Greek used in finance to measure the sensitivity of an option's value to a one-percent change in the implied volatility of the underlying asset.

- The trader checked the kappa of his portfolio to see how a jump in market fear would affect his profits.
- While most traders refer to this risk metric as vega, some academic texts and specific trading desks still use the term kappa.

Usage: Often used interchangeably with 'vega' in professional finance contexts.

## Examples

- I definitely enjoy waking up at 5 a.m. every day, kappa.
- He told the chat he was the best player in the world, kappa, and everyone laughed at the joke.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.