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Webster 1828 Edition

, a.

Not reclaimed from wildness; not domesticated; not made familiar with man; as an untamed beast.

Not subdued; not brought under control; as a turbulent, untamed mind.

Not softened or rendered mild by culture; as an untamed people.

untamed ‎(comparative more untamed, superlative most untamed)

Wild, uncontrolled, especially of animals not domesticated or trained to human contact.
The mustang is an untamed horse that roams where it wants, with little interest in humans.
- 2013 November 27, John Grotzinger, “The world of Mars [print version: International Herald Tribune Magazine, 2013, p. 36]”, in The New York Times:
  John Wesley Powell ... the one-armed Civil War veteran led nine men in four wooden dories down the untamed and uncharted Colorado River and into the equally untamed and uncharted Grand Canyon.

Wild, uncontrolled, especially of animals not domesticated or trained to human contact