The term grid has several meanings in various fields:

• in mathematics and geometry, a grid is a system of two sets of lines that intersect each other at a fixed angle, usually a right angle (i.e. a set of vertical lines and a set of horizontal lines). This usage applies to urban studies and planning; see grid plan;
• in electrical engineering,
  • a transmission grid is a high-voltage network for long-distance electric power transmission;
  • a distribution grid is a medium- and low-voltage network for local distribution of electric power to end-users;
  • a grid is an element within a triode vacuum tube which controls the flow of current through the device;
• in computer architecture, the word grid sometimes refers to a network with a topology similar to a grid: see grid computing;
• in Norse mythology, Grid was a giantess who knew that Loki was trying to trick Thor into being killed by Geirrod. She gave Thor her iron gloves and magical belt and staff to fight the frost giant.
• AIDS was known as GRID (Gay-related immune deficiency) until 1982.