c. 1200 (late 12c. as a surname), sergeaunt, also sergiaunte, serjainte, sergunt, cerjaunt, etc., "a servant, servingman," especially "an officer in a lord's retinue," from Old French sergent, serjant "(domestic) servant, valet; court official; soldier," from Medieval Latin servientum (nominative serviens) "servant, vassal, soldier" (in Late Latin "public official"), from Latin servire "to serve" (see serve (v.)).
The Latin word also is the source of Spanish sirviente, Italian servente. Sergeant is thus essentially a doublet of servant, and 16c. writers in English sometimes use the two words interchangeably.
By c. 1300 in a feudal sense of "tenant by military service under the rank of knight;" the modern military meaning "non-commissioned military officer" is recorded by 1540s. Originally a much more important position than after. As a police rank, in Great Britain from 1839.
The sense of "officer whose duty is to enforce judgments of a tribunal or legislative body" is from c. 1300 (hence sergeant at arms, attested from late 14c.).
The Middle English alternative spelling serjeant (from Old French) was retained in Britain in special use as the title of a superior order of barristers from which Common Law judges were chosen (mid-14c.); in this use it is from the legal Latin phrase serviens ad legem, "one who serves (the king) in matters of law"). It was also used of certain other officers of the royal household.
Fem. form sergeantess is attested from mid-15c. Sergeant-major is attested from 1570s. The sergeant-fish (1871) so-called for lateral markings resembling a sergeant's stripes. Related: Sergeancy.
c. 1200, servaunt, "male or female personal or domestic attendant, one owing duty of service to a master or lord, one employed by another and subject to his orders," from Old French servant "servant; foot-soldier," noun use of servant "serving, waiting," present participle of servir "to attend, wait upon" (see serve (v.)).
From early 14c. as "a slave," also used of bees. In North American colonies and in U.S., it was the usual designation for "slave" 17c.-18c. (in 14c.-15c. and later in Biblical translations the word often was used to render Latin servus, Greek doulos "slave").
Also in Middle English "professed lover, one devoted to the service of a lady" (mid-14c.). In 14c.-16c. sometimes confused with sergeant. Public servant is attested from 1670s. Wyclif (late 14c.) has servauntesse "female slave, maidservant, handmaiden."
"swindler, impostor," c. 1600; also "one easily cheated" (1640s); "a swindle, trick, sham, imposition" (1708), an obsolete word said to be from Turkish chaush "sergeant, herald, messenger," but the sense connection is obscure. Century Dictionary says the Turkish word is via Arabic khawas from Hindi khawas "an attendant." Also used as a verb, "to cheat, swindle" (1650s).
"to instruct in military exercise," 1620s (a sense also found in Dutch drillen and the Danish and German cognates), probably from drill (v.1) on the notion of troops "turning" in maneuvers. Related: Drilled, drilling.
As a noun, "act of training soldiers in military tactics," 1630s; the extended sense of "the agreed-upon procedure" is by 1940. Drill-sergeant "non-commissioned officer who instructs soldiers in their duties and trains them in military movements" is by 1760. Drill-master "one who gives practical instructions in military tactics" is by 1766.
Old English stæf (plural stafas), "walking stick, strong pole used for carrying, rod used as a weapon, pastoral staff," probably originally *stæb, from Proto-Germanic *stab- (source also of Old Saxon staf, Old Norse stafr, Danish stav, Old Frisian stef, Middle Low German and Middle Dutch staf, Old High German stab, German Stab, Gothic *stafs "element;" Middle Dutch stapel "pillar, foundation"), from PIE root *stebh- "post, stem, to support, place firmly on, fasten" (source also of Old Lithuanian stabas "idol," Lithuanian stiebas "staff, pillar;" Old Church Slavonic stoboru "pillar;" Sanskrit stabhnati "supports;" Greek stephein "to tie around, encircle, wreathe," staphyle "grapevine, bunch of grapes;" Old English stapol "post, pillar").
As "pole from which a flag is flown," 1610s. In musical notation from 1660s. Sense of "group of military officers that assists a commander" is attested from 1702, apparently from German, from the notion of the "baton" that is a badge of office or authority (a sense attested in English from 1530s); hence staff officer (1702), staff-sergeant (1811). Meaning "group of employees (as at an office or hospital)" is first found 1837. Staff of life "bread" is from the Biblical phrase break the staff of bread meaning "cut off the supply of food" (Leviticus xxvi.26), translating Hebrew matteh lekhem.
The Old English word, in plural, was the common one used for "letter of the alphabet, character," hence "writing, literature," and many compounds having to do with writing, such as stæfcræft "grammar," stæfcræftig "lettered," stæflic "literary," stæfleahtor "grammatical error," with leahtor "vice, sin, offense."