Definition of orchidacean in US English:

orchidacean

adjective

rare
  • Botany. Characteristic of orchids.

Origin

Late 19th century (in an earlier sense). From scientific Latin Orchidaceae, family name + -an. The noun does not have the expected sense for a word of this formation; compare -acean. With use as noun compare earlier orchidist. With use as adjective compare earlier (and more common) orchidaceous.

Pronunciation

orchidacean

/ˌɔːkɪˈdeɪʃn/