struthioniformes

from The Century Dictionary.

• In ornithology, in Sundevall's system of classification, a cohort of Gallinæ, composed of the South American tinamous, or Crypturi, and coextensive with the Dromæognathæ of Huxley: so called from their resemblance in some respects (notably palatal structure) to struthious birds.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a ratite bird order: ostriches and related extinct birds; known from the Pleistocene onward