The definition of listless is someone who is lacking in energy or vitality and does not extend physical effort.(adjective)
An example of someone who would be described as listless is a depressed person who lays around all day.
See listless in Webster's New World College Dictionary
Origin: list + -less
See listless in American Heritage Dictionary 4
Origin: Middle English listles
Origin: : probably from liste, desire (from listen, to desire; see list5)
Origin: + -les, -lesse, -less.
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