1660s, "a branding," from Greek stigmatizein, from stigmat-, stem of stigma (see stigma). Meaning "condition of being affected with stigmata" is from 1897.

Old English mearcung (Anglian mercung) "action of making marks, branding; mark, pattern of marks, characteristic; constellation," verbal noun from mark (v.). Related: Markings.

1540s, "heated metal used for burning or searing animal tissue," from Latin cauterium "branding iron," from Greek kauterion, from kauteriazein (see cauterize). From 1570s as "a burning or searing" (by a hot iron or caustic substance).

"to burn or sear (morbid flesh) with a hot iron," c. 1400, from Old French cauterisier, from Late Latin cauterizare "to burn or brand with a hot iron," from Greek kauteriazein, from kauter "burning or branding iron," from kaiein "to burn," a word of uncertain origin. Related: Cauterized; cauterizing.

of horses, cows, dogs, etc., "marked with streaks, streaked with a darker color," 1670s, a variant of Middle English brended (early 15c.), from bren "brown color" (13c.), noun from past participle of brennen "burn" (from Proto-Germanic *brennan "to burn," from PIE root *gwher- "to heat, warm"). The etymological sense of the adjective appears to be "marked as though by branding or burning." The form was altered perhaps by influence of kindled.

c. 1400, "to impress or burn a mark upon with a hot iron, cauterize; stigmatize," originally of criminal marks or cauterized wounds, from brand (n.). Figuratively, often in a bad sense, "fix a character of infamy upon," mid-15c., with the criminal marking in mind. As a means of marking ownership or quality of property, 1580s. Related: Branded; branding.

Old English brand, brond "fire, flame, destruction by fire; firebrand, piece of burning wood, torch," and (poetic) "sword," from Proto-Germanic *brandaz "a burning" (source also of Old Norse brandr, Old High German brant, Old Frisian brond "firebrand; blade of a sword," German brand "fire"), from PIE root *gwher- "to heat, warm."

The meaning "iron instrument for branding" is from 1828. The meaning "mark made by a hot iron" (1550s), especially on a cask, etc., to identify the maker or quality of its contents, had broadened by 1827 to include marks made in other ways, then to "a particular make of goods" (1854). Brand-name is from 1889; brand-loyalty from 1961. Old French brand, brant, Italian brando "sword" are from Germanic (compare brandish).

1867, "calf or yearling found without an owner's brand," a word from the great cattle ranches of the American West, so called for Samuel A. Maverick (1803-1870), Texas cattle owner who was notoriously negligent in branding his calves.

All neat stock found running at large in this State, without a mother, and upon which there is neither mark nor brand, shall be deemed a maverick, and shall be sold to the highest bidder for cash, at such time and place, and under such rules and regulations, as the round-up commissioners of the district shall prescribe. [act to amend the General Statutes of the State of Colorado, approved April 8, 1885]

The family name is an old one in Boston, and a different Samuel Maverick was killed in the Boston Massacre. The sense of "individualist, unconventional person" is said to be attested by 1886, via the notion of "masterless," but its modern popularity  seems to date to the late 1930s and the career of Maury Maverick (1895-1954) of Texas, grandson of Samuel the rancher and a Democratic congressman 1935-1939 famous for his liberal independent streak, who also coined gobbledygook.

"The Crisis" (April 1939) wrote that "During his stormy career in Washington Maverick became known as the one dependable liberal among the southerners. He recognized the broad problems of our nation, refusing to allow his vision to be limited by sectional prejudices, or racial or economic bugaboos. He was the only southern congressman to vote for the Gavagan federal anti-lynching bill. Not only did he vote for it, but he made a speech on the floor of the House in support of it."