Specific military sense of "army officer next in rank to a captain and commanding the company in his absence" is from 1570s. Pronunciation with lef- is common in Britain, and spellings to reflect it date back to 14c., but the origin of this is a mystery (OED rejects suggestion that it comes from old confusion of -u- and -v-).
"chief commander of a regiment of troops," 1540s, coronell, from French coronel (16c.), modified by dissimilation from Italian colonnella "commander of the column of soldiers at the head of a regiment," from compagna colonella "little column company," from Latin columna "pillar," collateral form of columen "top, summit" (from PIE root *kel- (2) "to be prominent; hill").
The French spelling was reformed late 16c. English spelling was modified 1580s in learned writing to conform with the Italian form (via translations of Italian military manuals), and pronunciations with "r" and "l" coexisted until c. 1650, but the earlier pronunciation prevailed. Spanish and Portuguese coronel, from Italian, show similar evolution by dissimilation and perhaps by influence of corona. Abbreviation col. is attested by 1707.
military rank above captain and below lieutenant colonel, 1640s, from French major, short for sergent-major, originally a higher rank than at present, from Medieval Latin major "chief officer, magnate, superior person," from Latin maior "an elder, adult," noun use of the adjective (see major (adj.)).
His chief duties consist in superintending the exercises of his regiment or battalion, and in putting in execution the commands of his superior officer. His ordinary position in the line is behind the left wing. [Century Dictionary, 1897]
The musical sense is attested by 1797.
1670s, "system of strict discipline," from the name of French military officer Jean Martinet (killed at the siege of Duisburg, 1672), lieutenant colonel in the Régiment du Roi, who in 1668 was appointed inspector general of the infantry. "It was his responsibility to introduce and enforce the drill and strict discipline of the French regiment of Guards across the whole infantry" [Olaf van Minwegen, "The Dutch Army and the Military Revolutions 1588-1688," 2006].
The meaning "an officer who is a stickler for discipline and regularity in small details" is first attested 1779 in English, but "No F[rench] use of the word in the sense of a disciplinarian appears" [Century Dictionary]. The surname is a diminutive of Latin Martinus (see Martin). Related: Martinetism.
see bunk (n.2). The North Carolina county was named for Edward Buncombe (1742–1778), North Carolina revolutionary leader and colonel in the American army.
1815, from the true Simon Pure "the genuine person or thing" (1795), from Simon Pure, name of a Quaker who is impersonated by another character (Colonel Feignwell) in part of the comedy "A Bold Stroke for a Wife" (1717) by Susannah Centlivre, English dramatist and actress. The real Simon Pure is dealt with as an impostor in the play and is believed only after he has proved his identity.