Talk:obscura

The etymologies for inflectional endings are: More information on PIE endings can be found on the unfinished appendix: Appendix:PIE declension. obscurus is an old word containing a Proto-Indo-European root that has not been transparently preserved in other Latin words (there are culus and cutis, both without the s-mobile s- and with different suffixes). Its inflection as a distinct adjective dates probably to Proto-Italic or late PIE. --Ivan Štambuk 08:27, 12 June 2010 (UTC)
 * 1) nominative and vocative singular feminine: PIE *-eh₂ (late PIE feminine marker) > Old Latin -ā > Classical Latin -a
 * 2) NAV neuter plural: PIE *-eh₂ (originally used to form collective nouns, but distinct than the previous suffix)
 * 3) ablative singular: Old Latin -ād (formed analogically to o-stem ending -ōd, which later yielded Classical Latin -ō) > Classical Latin > -ā

Citation available
The fairy tales of science/The Magic of the Sunbeam