half a mind

A moderate, irresolute, or indefinite inclination or intention. My flight home was so terrible, I have half a mind to write a letter to the airline company and complain. We set out on the road with only half a mind as to where we would go!

An inclination that is not definite or resolute. For example, I've half a mind to drop the course, or He went out with half a mind to walk all the way there. [First half of 1700s] Also see have a good mind to.

To be strongly inclined toward; to be somewhat inclined toward. The first term began life back in the fifteenth century as having a great mind to do something, as in “I have a great mynd to be a lecherous man” (John Bale, Kyng Johan, ca. 1550). In 1674 Lord Clarendon wrote in History of the Rebellion, “The duke of Lorrayne had a very good mind to get a footing in Ireland.” The second phrase, which implies indecision—half of one’s mind inclines one way and the other half the other way—was known by 1700 or so and appeared more and more often in the nineteenth century. “She had half a mind to reply,” wrote Edward Bulwer-Lytton (My Novel, 1853).