The Collaborative International Dictionary of English v.0.48:

Extraversion \Ex`tra*ver"sion\, n. [Pref. extra- + L. vertere,
   versum, to turn: cf. F. extraversion.]
   The act of throwing out; the state of being turned or thrown
   out. [Obs.] --Boyle.
   [1913 Webster]

WordNet (r) 3.0 (2006):

extraversion
    n 1: (psychology) an extroverted disposition; concern with what
         is outside the self [syn: extraversion, extroversion]
         [ant: ambiversion, introversion]