[1] : The Collaborative International Dictionary of English v.0.48

epi- \ep"i-\ gr. 'epi` on, upon, to; akin to skr. api besides,
   and prob. to l. ob to, before, on account of, and perh. to e.
   of, off.
   a prefix, meaning upon, beside, among, on the outside, above,
   over. it becomes ep-before a vowel, as in epoch, and
   eph-before a greek aspirate, as in ephemeral.
   1913 webster

[2] : WordNet (r) 2.0

epi
     n : a self-report personality inventory based on hans eysenck's
         factor analysis of personality which assumes three basic
         factors the two most important being extraversion to
         introversion and neuroticism syn: eysenck personality
         inventory
see also:
eysenck personality inventory 

Epi- >> E Words
Epi-, definition of term: Epi-
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