mid-14c., "keep back or in store for future use;" late 14c., "keep as one's own," from Old French reserver "set aside, withhold" (12c.) and directly from Latin reservare "keep back, save up; retain, preserve," from re- "back" (see re-) + servare "to keep, save, preserve, protect" (from PIE root *ser- (1) "to protect"). Meaning "to book" is from 1935. Related: Reserved; reserving.
1640s, as a theological term (in reference to "covenants" between God and man), from French fédéral, an adjective formed from Latin foedus (genitive foederis) "covenant, league, treaty, alliance" (from PIE *bhoid-es-, suffixed form of root *bheidh- "to trust, confide, persuade").
Secular meaning "pertaining to a covenant or treaty" (1650s) led to political sense of "formed by agreement among independent states" (1707), from use of the word in federal union "union based on a treaty" (popularized during formation of U.S.A. 1776-1787) and like phrases. Also from this period in U.S. history comes the sense "favoring the central government" (1788) and the especial use of the word (as opposed to confederate) to mean a state in which the federal authority is independent of the component parts within its legitimate sphere of action. Used from 1861 in reference to the Northern forces in the American Civil War.
1610s, "something stored up," from reserve (v.) or from French réserve, a back-formation from reserver "set aside, withhold," from Latin reservare "keep back, save up; retain, preserve," from re- "back" (see re-) + servare "to keep, save, preserve, protect" (from PIE root *ser- (1) "to protect").
Meaning "self-imposed restraint on freedom of words or actions; habit of keeping back the feelings" is from 1650s. The meaning "district or place set apart for some particular use" is by 1805. The sense of "amount of capital kept on hand to meet probable expenses or demand" is by 1866. That of "amount of natural resources known to exist in a particular region" is by 1912. As an adjective, "kept in reserve," by 1719.
The military sense of "body of troops withheld from action to serve as reinforcements, etc." is from 1640s; that of "national emergency defense or auxiliary military force" (reserves) is by 1866.
U.S. Federal Communications Commission, formed 1934 from the former Federal Radio Commission.
1788, "doctrine of federal union in government," American English, from French fédéralisme, from fédéral (see federal). Also, from about the same time and place, "doctrines of the Federalist Party in American politics."
1540s, from Latin subsidiarius "belonging to a reserve, of a reserve, reserved; serving to assist or supplement," from subsidium "a help, aid, relief, troops in reserve" (see subsidy). As a noun, c. 1600, "subsidiary thing." In Latin the word was used as a noun meaning "the reserve."
by 1992, vaguely from Federal Home Loan Mortgage Corporation.
U.S. Federal Bureau of Investigation, formed 1935 from the former United States Bureau of Investigation (1908).