e·con·o·my 
(ĭ-kŏnə-mē)
(ĭ-kŏnə-mē)n. pl. e·con·o·mies
1.
a. Careful, thrifty management of resources, such as money, materials, or labor: learned to practice economy in making out the household budget.
b. An example or result of such management; a saving.
2.
a. The system or range of economic activity in a country, region, or community: Effects of inflation were felt at every level of the economy.
b. A specific type of economic system: an industrial economy; a planned economy.
3. An orderly, functional arrangement of parts; an organized system: "the sense that there is a moral economy in the world, that good is rewarded and evil is punished" (George F. Will).
4. Efficient, sparing, or conservative use: wrote with an economy of language.
5. The least expensive class of accommodations, especially on a commercial conveyance, such as an airplane.
6. Theology The method of God's government of and activity within the world.
adj.
Economical or inexpensive to buy or use: an economy car; an economy motel.
[Middle English yconomye, management of a household, from Latin oeconomia, from Greek oikonomiā, from oikonomos, manager of a household : oikos, house; see weik-1 in the Appendix of Indo-European roots + nemein, to allot, manage; see nem- in the Appendix of Indo-European roots.]