Gamma is the third letter of the Greek alphabet. In the Ionian number system, it meant the number 3. It originated from the Phoenician letter gaml [U:10902]. Many other Latin and Cyrillic letters (G, C, Г ...) originated from the same scale.

A lower case Greek gamma letter is widely used in scientific notation (in mathematics, physics, astronomy).

In geometry, when specifying angles, they are usually used in the order of alpha, beta, and gamma.

Gamma radiation (γ-rays) - electromagnetic radiation in the extremely short-wavelength range.

"Gamma" is often part of the stars' name (γ Centauri - Gamma Centauri), usually indicates their relative luminosity (alpha is the brightest star in the constellation, beta, and gamma dimmer).