Definition of polymyodian in US English:

polymyodian

adjective

Ornithology
rare, historical
  • Of a bird: having a syrinx with several distinct muscles; specifically (in Müller's scheme) belonging to the division Polymyodi of passerine birds, nearly corresponding to the suborder Oscines (the songbirds).

Origin

Mid 19th century; earliest use found in Proceedings of the Zoological Society of London. From scientific Latin Polymyodi, former group name + -an.

Pronunciation

polymyodian

/ˌpɒlɪmʌɪˈəʊdɪən/