\Ra*ti"t[ae]\, n. pl. [NL., fr. L. ratis a raft; cf. L.
ratitus marked with the figure of a raft.] (Zo["o]l.)
An order of birds in which the wings are small, rudimentary,
or absent, and the breastbone is destitute of a keel. The
ostrich, emu, and apteryx are examples.