1. enlargement, increase, spread; development. expansion\ex*pan"sion\ , n. [l. expansio: cf. f. expansion.].
2. the act of expanding or spreading out; the condition of being expanded; dilation; enlargement.
3. that which is expanded; expanse; extend surface; as, the expansion of a sheet or of a lake; the expansion was formed of metal. the starred expansion of the skies.
4. space through which anything is expanded; also, pure space. lost in expansion, void and infinite. more.
5. (com.) enlargement or extension of business transactions; esp., increase of the circulation of bank notes.
6. (math.) the developed result of an indicated operation; as, the expansion of (a + b)2 is a2 + 2ab + .
7. 6. (steam engine) the operation of steam in a cylinder after its communication with the boiler has been cut off, by which it continues to exert pressure upon the moving piston.
8. (nav. arch.) the enlargement of the ship mathematically from a model or drawing to the full or building size, in the process of construction. am. nav. encyc.note: expansion is also used adjectively, as in expansion joint, expansion gear, etc.expansion curve, a curve the co?rdinates of which show the relation between the pressure and volume of expanding gas or vapor; esp. (steam engine), that part of an indicator diagram which shows the declining pressure of the steam as it expands in the cylinder.expansion gear (steam engine). a cut-off gear. see:
illust. of link motion.
9. The act of expanding or spreading out; the condition of being expanded; dilation; enlargement.
10. That which is expanded; expanse; extend surface; as, the expansion of a sheet or of a lake; the expansion was formed of metal.
11. Space through which anything is expanded; also, pure space.
12. Enlargement or extension of business transactions; esp., increase of the circulation of bank notes.
13. The developed result of an indicated operation; as, the expansion of 2 is a2 + 2ab + b2.
14. The operation of steam in a cylinder after its communication with the boiler has been cut off, by which it continues to exert pressure upon the moving piston.
15. The enlargement of the ship mathematically from a model or drawing to the full or building size, in the process of construction. the act of increasing in size or volume or quantity or scope adding information or detail a discussion that provides additional information.
16. Expansion is the process of becoming greater in size, number, or amount. the rapid expansion of private health insurance. a new period of economic expansion = growth.