Thoughtless

Part of speech: adverb (adv.)

1. Lacking thought; careless; inconsiderate; rash; as, a thoughtless person, or act.

2. Giddy; gay; dissipated. [R.] Johnson.

3. Deficient in reasoning power; stupid; dull. Thoughtless as monarch oaks that shade the plain. Dryden. -- Thought"less*ly, adv. -- Thought"less*ness, n.