(from the article `introvert and extravert`) ...is now regarded as overly simplistic because almost no one can be accurately described as wholly introvert or extravert. Most persons fall ...
One who falls between the two extremes of introversion and extroversion, possessing some of the tendencies of each. ... (05 Mar 2000) ... 
Type: Term Pronunciation: am′bi-vert Definitions: 1. One who falls between the two extremes of introversion and extroversion, possessing some tendencies of each.
ambivert 1. Someone who is intermediate between an extrovert and an introvert. 2. A personality trait including the qualities of both introversion and extroversion.
one whose personality type is intermediate between extrovert and introvert.