mid-12c., "large group of people," from Old French compagnie "society, friendship, intimacy; body of soldiers" (12c.), from Late Latin companio, literally "bread fellow, messmate," from Latin com "with, together" (see com-) + panis "bread," from PIE root *pa- "to feed." Abbreviation co. dates from 1670s.
Meaning "companionship, consort of persons one with another, intimate association" is from late 13c. Meaning "person or persons associated with another in any way" is from c. 1300. In Middle English the word also could mean "sexual union, intercourse" (c. 1300).
From late 14c. as "a number of persons united to perform or carry out anything jointly," which developed a commercial sense of "business association" by 1550s, the word having been used in reference to trade guilds from late 14c. Meaning "subdivision of an infantry regiment" (in 19c. usually 60 to 100 men, commanded by a captain) is from c. 1400.
Meaning "person or persons with whom one voluntarily associates" is from c. 1600; phrase keep company "consort" is from 1560s (bear company in the same sense is from c. 1300). Expression two's company "two persons are just right" (for conversation, etc.), is attested from 1849; the following line varies: but three is none (or not), 1849; three's trumpery (1864); three's a crowd (1856).
late 14c., publike, "open to general observation," from Old French public (c. 1300) and directly from Latin publicus "of the people; of the state; done for the state," also "common, general, of or belonging to the people at large; ordinary, vulgar," and as a noun, "a commonwealth; public property." This Latin word was altered (probably by influence of Latin pubes "adult population, adult;" see pubis) from Old Latin poplicus "pertaining to the people," from populus "people" (see people (n.)).
Attested in English from early 15c. as "of or pertaining to the people at large" and from late 15c. as "pertaining to public affairs." The meaning "open to all in the community, to be shared or participated in by people at large" is from 1540s in English. An Old English adjective in this sense was folclic. The sense of "done or made by or on behalf of the community as a whole" is by 1550s; that of "regarding or directed to the interests of the community at large, patriotic" is from c. 1600.
Public relations "the management of the relationship between a company or corporation and the general public" is recorded by 1913 (with an isolated use by Thomas Jefferson in 1807). Public office "position held by a public official" is from 1821; public service is from 1570s; public interest "the common well-being" is from 1670s. Public enemy, one considered a nuisance to the general community, is attested from 1756. Public sector attested from 1949. Public funds (1713) are the funded debts of a government.
Public woman "prostitute" is by 1580s, on the notion of "open for the use of all." For public house, see pub.
"the general body of people constituting a nation, state, or community; the nation or state," 1610s, from public (adj.); the meaning "people in general" is from 1660s. In public "in open view, publicly, before the people at large" is attested from c. 1500.
1570s, originally, in Britain, "a grammar school endowed for the benefit of the public," but most have evolved into boarding-schools for the well-to-do. From public (adj.) + school (n.1). The main modern meaning in U.S., "school (usually free) provided at public expense and run by local authorities," is attested from 1640s.
"disposition to promote the public interest, public spirit," 1690s, from public (adj.) in the sense of "directed to the interests of the community at large."
"having a disposition to promote the interests or advantage of a community," 1670s, from public (adj.) in the sense of "directed to the interests of the community at large." Related: Public-spiritedness.
"the executive branch of the public service," as distinguished from the military, naval, legislative, or judicial, 1765, originally in reference to non-military staff of the East India Company, from civil in the sense "not military." Civil servant is from 1792.