Wiktionary
zestless
a. Lacking zest; passionless, unenthusiastic.
Usage examples of "zestless".
For a month or two the murderee had sat smoking cigarettes in the zestless grotto off Fulham Broadway.
Giles looked around as if for the last time at his empty room, sniffed, gave Quentin a zestless smile, and moved with awkward caution out of the door.