apterium
nounEtymology From a- + Ancient Greek πτερόν (pterón, “feather”) + -ium. Compare Ancient Greek ἄπτερος (ápteros, “featherless”).
1
Biology, Natural sciences, Ornithology An area of bare (featherless) skin on a bird.
- The two halves of the lower cervical tract are still separated by an apterium 4 mm. wide, as in the young bird, but contour feathers are now present on the chin and upper throat, so that they are united at their upper ends.1918, American Ornithologists' Union, The Auk:
- Coordinate terms
- pteryla