introversion

Noun

• (psychology) an introverted disposition; concern with one's own thoughts and feelings

• the folding in of an outer layer so as to form a pocket in the surface
  • the invagination of the blastula
    

• the condition of being folded inward or sheathed

Related words

• Synonyms: 
  invagination , intussusception , infolding
• Antonyms: 
  ambiversion , extraversion , extroversion