|Noah Webster's Dictionary|
1. (a.) Not thinking; not heedful; thoughtless; inconsiderate; as, unthinking youth.
2. (a.) Not indicating thought or reflection; thoughtless.
Unthinking (2 Occurrences)
Luke 11:40 unthinking! did not He who made the outside also the inside make? (YLT)
Luke 12:20 And God said to him, Unthinking one! this night thy soul they shall require from thee, and what things thou didst prepare -- to whom shall they be? (YLT)