Definition of subsexual in US English:

subsexual

adjective

  • Genetics. Of or relating to any of several forms of apomixis in plants in which the progeny are genetically different from the parent despite the lack of fertilization; specifically designating or characterized by a form of parthenogenesis in which the embryo develops from a cell produced by a modified form of meiosis, involving chromosome pairing and recombination but no reduction in the number of chromosomes.

Origin

Mid 19th century (in an earlier sense). From sub- + sexual.