half a heart, with

with half a heart

With only a little or moderate amount of enthusiasm or interest; in an uninspired manner; halfheartedly. You can't go out and play with half a heart and expect to win. You have to play with everything you've got!
See also: half, heart

half a heart, with

With only moderate enthusiasm, as in After his transfer he worked with half a heart, looking forward to early retirement. [Mid-1800s] For an antonym, see with all one's heart.
See also: half