introverted

adjective4

1. •
   Turned or thrust inward
2. •
   Thinking about internal or spiritual matters.

   • ...Self-searching with an introverted eye... — 1782
3. •
   Of or characteristic of the personality of an introvert: thoughtful, reflective.

   • An extraverted individual can hardly understand the necessity that forces the introverted to accomplish his adaptation by first formulating a general conception. — 1915
4. •
   Arranged so that two similar words, lines, etc. form the middle of the structure.

   • In the Quatrain Reversed or Introverted, the first line corresponds with the fourth. — 1896