The Collaborative International Dictionary of English v.0.48:

Self-fertilization \Self`-fer`ti*li*za"tion\, n. (Bot.)
   The fertilization of a flower by pollen from the same flower
   and without outer aid; autogamy.
   [1913 Webster]

WordNet (r) 3.0 (2006):

self-fertilization
    n 1: fertilization by the union of male and female gametes from
         the same individual [syn: self-fertilization, self-
         fertilisation] [ant: cross-fertilisation, cross-
         fertilization]