Definition of obpyramidal in US English:

obpyramidal

adjective

Botany
  • Inversely pyramidal; of the form of an inverted pyramid.

Origin

Mid 19th century; earliest use found in George Bentham (1800–1884), botanist. From ob- + pyramidal.

Pronunciation

obpyramidal

/ɒbpɪˈramɪdl/