self-willed
adjective
Definitions
Obstinate; strong-minded; unyielding to the desires, concern or opinions of others.
Example: He was so self-willed that he refused to do anything that did not grant instant satisfaction or direction.
Possessing self-will; determined to pursue one's own desires or adhere to one's own opinion..
Example: The idea of self-willed machines, which could decide to take over the world, scares all the people smart enough to create such devices.