Definition of radiatiform in US English:

radiatiform

adjective

Botany
rare
  • Of a flower head: apparently radiate; having ray flowers at the margin of the disk, or marginal tubular flowers that are larger than the inner ones.

Origin

Mid 19th century; earliest use found in John Balfour (1808–1884), botanist. From radiate + -iform.

Pronunciation

radiatiform

/ˌreɪdɪˈeɪtɪfɔːm/