<p><strong>Noun:</strong></p><ul><li>A separable component, frequently one that is interchangeable with others, for assembly into units of differing size, complexity, or function.</li><li>Any of the individual, self-contained segments of a spacecraft, designed to perform a particular task: the spacecraft's command module; a lunar module.</li><li>A standard or unit for measuring.</li><li>A selected unit of measure, ranging in size from a few inches to several feet, used as a basis for the planning and standardization of building materials.</li><li>Mathematics: an Abelian group with a set of left or right operators forming a ring such that for any two operators and any group element the result of having the first operator act on the element, giving a second element, and the second operator act on the second element is equal to the result of having a single operator, formed by adding or multiplying the two operators, act on the first element.</li><li>Computers: part of a program that performs a distinct function.</li><li>An interchangeable, plug-in hardware unit.</li></ul>