ambiversive

from WordNet (r) 3.0 (2006)

ambiversive
    adj 1: intermediate between introversive and extroversive [ant:
           {extraversive}, {extroversive}, {introversive},
           {introvertive}]

from The Collaborative International Dictionary of English v.0.48

ambiversive \ambiversive\ adj.
   1. (Psychol.) intermediate between introversive and
      extroversive. Contrasted to {introversive} and
      {extroversive}.
      [WordNet 1.5]

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