late 14c., "fact of being useful," from Old French utilite "usefulness" (13c., Modern French + utilité), earlier utilitet (12c.), from Latin utilitatem (nominative utilitas) "usefulness, serviceableness, profit," from utilis "usable," from uti "make use of, profit by, take advantage of" (see use (v.)). Meaning "a useful thing" is from late 15c. As a shortened form of public utility it is recorded from 1930.
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).
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.
"imaginary average American citizen," 1934; the Q perhaps suggested by John Quincy Adams.
by 1988, an abbreviation of sport/utility vehicle (itself attested from 1982).
"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.