A Maverick is defined as a nonconformist. Usually a person with unorthodox or independent views.
It’s an eponymous word after Samuel Maverick (1803-1870), a Texas rancher who chose not to brand his cattle. As mayor of San Antonio in the mid- 1800's the small town politician accepted a herd of 400 cattle in 1847 in payment of a debt but left them in the care of one of his men who allowed the steers to roam on his ranch unbranded. One can almost hear the locals upon discovering one of these roving unbranded livestock. ”Oh, that’s one of Maverick’s” which probably became shortened to, “That’s a Maverick.”
From then on any unbranded cow, steer, and especially calves that grow up and became separated from their mothers without a brand to tell who owns them has been dubbed a Maverick.
During the early 1800’s in the United States ownership of cattle was determined by the brand, so the name mavericks came to be given to all unmarked calves caught when straying from the herd. Neglected and allowed to run wild, these calves were rounded up and branded by other ranchers. Because the range was large, a few cattle more or less made little difference to the big ranchmen.
The practice, though dishonest, soon became generally accepted on the range. As this became a customary way of life, many newcomers to the West were able to accumulate a herd "with nothing but a branding iron." First recorded 1886, as the notion of "masterless" and then eventually leading to independent minded humans, became known as mavericks.
In 1957 Mr. Maverick's name was borrowed by the producers of the classic "Maverick" TV show with the enduring James Garner as the starring character. Along with a couple of brothers named Maverick, they all lived by their wits in the Wild West.