A self-contained component of a system, often interchangeable, which has a well-defined interface to the other components.

(architecture) A standard unit of measure used for determining the proportions of a building.

(programming) A section of a program; a subroutine or group of subroutines.

A unit of education covering a single topic.

A pre-prepared adventure scenario with related materials for a role-playing game.

(algebra, ring theory) An abelian group equipped with the operation of multiplication by an element of a ring (or another of certain algebraic objects), representing a generalisation of the concept of vector space with scalar multiplication.

(fractal geometry, mathematics) A fractal element.

(music) A file containing a music sequence that can be played in a tracker (called also mod or music module).

(hydraulics) A contrivance for regulating the supply of water from an irrigation channel.

(astronautics) An independent self-contained unit of a spacecraft.