noun

• One who, or that which, generates, begets, causes, or produces.
• (chemistry) An apparatus in which vapour or gas is formed from a liquid or solid by means of heat or chemical process, as a steam boiler, gas retort etc.
• (music) The principal sound or sounds by which others are produced; the fundamental note or root of the common chord; -- see also generating tone.
• (mathematics) An element of a group that is used in the presentation of the group: one of the elements from which the others can be inferred with the given relators.
• (geometry) One of the lines of a ruled surface; more generally, an element of some family of linear spaces.
• (programming) A subordinate piece of code which, given some initial parameters, will generate multiple output values on request.
• A piece of apparatus, equipment, etc, to convert or change energy from one form to another.
• Especially, a machine that converts mechanical energy into electrical energy.