1. In a thoughtless manner
   "he stared thoughtlessly at the picture"
   - unthinkingly, unthinking 
2. Showing thoughtlessness
   "he treated his parents thoughtlessly"

See also: thoughtless

Antonym: thoughtfully

• ambitionless
• ambitious
• ambitiously
• ambitiousness
• comatulid
• Comatulidae
• comb
• comb jelly
• comb-footed spider
• comb-like
• comb-out
• comb-plate
• combat
• combat area
• combat boot
• combat casualty
• combat ceiling
• combat fatigue
• combat injury
• combat intelligence
• combat mission
• combat neurosis
• combat pay
• combat pilot
• combat ship