Definition of epi- in English:

epi-

(also ep-)

prefix

  • 1On; upon.

    ‘epicycle’
    ‘epigraph’
  • 2Above.

    ‘epicotyl’
    ‘epicontinental’
  • 3In addition.

    ‘epigenesis’
    ‘epiphenomenon’

Origin

From Greek epi upon, near to, in addition.