sugár

Sugár is a Hungarian noun meaning a ray or beam. In geometry it denotes a half-line that starts at a given point and extends indefinitely in a single direction. In physics and optics, sugár refers to a stream of energy that travels from a source, such as a beam of light or a ray of radiation. The term is used in both everyday language and technical contexts.

In common expression, examples include fénysugár (a ray of light) and röntgensugár (X-ray). The related adjective sugárzó describes something that radiates, as in sugárzó fény. In engineering and aeronautics, compounds such as sugárhajtás (jet propulsion) and sugárhajtómű (jet engine) show the productive use of the word to denote directed energy or propulsion.

In geometry, sugár is defined as a part of a line with a fixed starting point and extending in one direction, contrasted with the entire line. In analytic geometry it is used to specify a direction from a point, often represented by a direction vector. The concept is foundational in teaching basic geometry and in ray tracing algorithms.