superfecundation

from WordNet (r) 3.0 (2006)

superfecundation
    n 1: fertilization of two or more ova released during the same
         menstrual cycle by sperm from separate acts of coitus
         (especially by different males)

from The Collaborative International Dictionary of English v.0.48

Superfecundation \Su`per*fec`un*da"tion\, n. (Physiol.)
   Fertilization of two ova, at the same menstruation, by two
   different acts of coition.
   [1913 Webster]

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