Synonyms of the word 
LISTLESS → DISPIRITED - LETHARGIC - SPIRITLESS
listless
- adj. Lacking energy, enthusiasm, or liveliness.
dispirited
- v. simple past tense and past participle of dispirit.
- adj. Without energy, gusto or drive, enervated, without the will to accomplish, disheartened.
lethargic
- adj. sluggish, slow.
- adj. indifferent, apathetic.
spiritless
- adj. Lacking energy, drive, motivation or emotion. Enervated.
If you are interested in words, visit the following sites :
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- 1word.ws/listless to play with words, suffixs, prefixs, etc.