Definition of semispecies in US English:

semispecies

noun

Biology
  • A subdivision of a species, especially one regarded as having more individuality than does a subspecies; specifically each of two or more biological subspecies (or species) that together constitute a superspecies.

Origin

Early 19th century. From semi- + species, apparently originally after German Halbart, lit. ‘half-species’.

Pronunciation

semispecies

/ˈsɛmɪˌspiːʃɪz/