from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Plural form of apterium.
from the GNU version of the Collaborative International Dictionary of English
- n.pl. Naked spaces between the feathered areas of birds. See pteryliæ.
from The Century Dictionary and Cyclopedia
- n. Plural of apterium.
Sorry, no etymologies found.
Only among breeders of domestic poultry and female Greater Sage-Grouse (Centrocercus urophasianus) does there seem to be a preference for big-breasted birds; in the case of sage-grouse, the males have developed an elaborate courtship display that exaggerates the size of the breast by expansion of large esophageal pouches and partial extension of cervical apteria (i.e., unfeathered areas between feather tracts), with larger-breasted males attracting and mating with more females.
It is interesting to note that the feathers on the bodies of the flying birds are arranged in tracts, with intervals here and there of quite, or almost, bare skin, called "apteria."