Extension

noun

1. The act of extending; a stretching out; enlargement in length or breadth; an increase
2. The state of being extended
3. That property of a body by which it occupies a portion of space (or time, e.g. "spatiotemporal extension")
4. A part of a building that has been extended from the original
5. Capacity of a concept or general term to include a greater or smaller number of objects; — correlative of intension.