The term "unbent" refers to something that is not curved or bent. Therefore, its antonyms will be words that describe the opposite behavior, such as bent, curved, twisted, contorted, crooked, and warped. These antonyms could be used to describe physical objects such as wires, pipes, or trees as well as the figurative use of the word "unbent," such as in the sense of being inflexible, stubborn, or unyielding. To convey the opposite meaning of "unbent," one could use these antonyms to describe something that's been bent or shaped in a particular direction or that's deviated from its original form or path.