set one's heart on

set (one's) heart on (something)

To resolutely determine to do or acquire something. When I was a little boy, I set my heart on becoming a fighter pilot. When Janie sets her heart on a new toy, she won't give us a moment's peace until we buy it for her.
See also: heart, on, set
Farlex Dictionary of Idioms.

set one's heart on

Also, have one's heart set on. Strongly desire something, as in I'd set my heart on a vacation in New Mexico but got sick and couldn't go, or Harry had his heart set on a new pickup truck. [Late 1300s]
See also: heart, on, set
The American Heritage® Dictionary of Idioms by Christine Ammer.

set one's heart on, to

To have an earnest desire for; to determine to obtain something. The heart has long been equated with one’s innermost being, and to “set” it on something means to fix it in that direction. This term dates from the fourteenth century. It appears in the Bible: “If riches increase, set not your heart upon them” (Psalms 62:10). This passage is repeated in the Book of Common Prayer.
See also: heart, set
The Dictionary of Clichés by Christine Ammer
See also:
  • set (one's) heart on (something)
  • set heart on
  • set your heart on
  • set your heart on something
  • set your heart/mind on something/on doing something
  • (one's) heart is set against (something)
  • one's heart is set against
  • have a heart
  • with all heart
  • with all my heart