The strength of will to carry out one's decisions, wishes, or plans.(noun)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "willpower" in a sentence
"Indeed, any attempt to alter compulsive or addictive behaviour by willpower is not only doomed to failure, but highly-destructive to the psychological wellbeing of the client."
"The idea of exercising willpower is seen in military boot camp, where recruits are trained to overcome one challenge after another."
"I would argue that, in addition to diet and exercise, willpower is also required."