halfhearted

adjective2

1. •
   Lacking full energy, effort, commitment, or resolve.

   • He made a halfhearted attempt to read the chapter before giving up and dozing off.
2. •
   (no longer used) Lacking in heart or beneficence; ungenerous; unkind.

   • such animals, Half-hearted creatures, as these are, your fox there — 1632