Definition of pseudomonocotyledonous in US English:

pseudomonocotyledonous

adjective

Botany
  • (Of a dicotyledonous plant) apparently monocotyledonous, as by the fusion of the two cotyledons, or by the abortion of one of them.

Origin

Mid 19th century; earliest use found in John Lindley (1799–1865), botanist and horticulturist. After post-classical Latin pseudo-monocotyledoneus.