lackadaisical (adj.)

• apathetic
• ataractic
• backward
• benumbed
• blase
• bored
• careless
• casual
• cold
• cool
• dead
• debilitated
• degage
• devil-may-care
• dilatory
• disinterested
• dispassionate
• dopey
• dormant
• droopy
• drugged
• dull
• easy
• easygoing
• emasculated
• enervated
• exanimate
• faineant
• heavy
• heedless
• idle
• inactive
• inanimate
• inattentive
• incurious
• indifferent
• indolent
• inert
• insouciant
• jaded
• laggard
• lagging
• languid
• languorous
• lax
• lazy
• leaden
• lethargic
• lifeless
• limp
• listless
• lukewarm
• lumpish
• mindless
• moribund
• negligent
• nonchalant
• numb
• offhand
• passive
• perfunctory
• phlegmatic
• reckless
• regardless
• remiss
• romantic
• sated
• sentimental
• slack
• sleepy
• slothful
• slow
• sluggish
• somnolent
• spiritless
• stagnant
• supine
• tepid
• torpid
• uncaring
• unconcerned
• undiscriminating
• unemotional
• unenthusiastic
• unexcitable
• unexcited
• unimpressed
• uninspired
• uninterested
• unmindful
• unmoved
• vegetative
• wan
• weary
• world-weary