Gamma

1. The third letter of the Greek alphabet (Γ, γ), preceded by beta (Β, β) and followed by delta, (Δ, δ).
2. The Gamma function, symbolized by Γ.
3. A constant approximately equal to 0.55721566, symbolized by γ (also known as the Euler–Mascheroni constant).
4. A non-SI unit of measure of magnetic flux density, equal to 1 nT.
5. (industries) slope of log-log plot of video input and luminance output.
6. A second-order measure of derivative price sensitivity, expressed as the rate of change in delta with respect to changes in the underlying asset price.

noun

A nonlinear operation used to encode and decode luminance or tristimulus values in video or still image systems.