Cowgill's law, named after Indo-Europeanist Warren Cowgill, refers to two unrelated sound changes, one occurring in Proto-Greek and the other in Proto-Germanic.
In Proto-Greek, Cowgill's law[1] says that a former pronounced as //o// vowel becomes pronounced as //u// between a resonant (pronounced as //r//, pronounced as //l//, pronounced as //m//, pronounced as //n//) and a labial consonant (including labiovelars), in either order.
Examples:
Note that when a labiovelar adjoins an pronounced as //o// affected by Cowgill's law, the new pronounced as //u// will cause the labiovelar to lose its labial component (as in Greek, Modern (1453-);: núks and Greek, Modern (1453-);: ónuks/ónukh-, where the usual Greek change *pronounced as //kʷ// > pronounced as //p// has not occurred).
Cowgill's law in Germanic[2] has no relation to Cowgill's law in Greek other than having been named after the same person. It says that a PIE laryngeal pronounced as //h₃//, and possibly pronounced as //h₂//, turns into pronounced as //k// in Proto-Germanic when directly preceded by a sonorant and followed by pronounced as //w//. This law is still controversial, although increasingly accepted. Donald Ringe (2006) accepts it;[2] Andrew Sihler (1995) is noncommittal.[1]
Examples are fairly few:
The first two examples, however, have good alternative explanations which don't involve Cowgill's law:
If the sound law becomes generally accepted, the relative chronology of this law could have consequences for a possible reconstructed phonetic value of pronounced as //h₃//. Since Germanic pronounced as //k// results from earlier PIE pronounced as //g//, and since the change occurred before Grimm's law applied (according to Ringe), the resulting change would be actually pronounced as //h₃w// > pronounced as //gʷ//. This would have been more likely if pronounced as //h₃// was a voiced velar obstruent to begin with. If pronounced as //h₃// was a voiced labiovelar fricative as is occasionally suggested, the change would therefore have been: pronounced as //ɣʷw// > pronounced as //ɡʷ//.
. Donald Ringe. From Proto-Indo-European to Proto-Germanic. Oxford University Press . 2006 . 978-0-19-955229-0.
. Andrew L. Sihler. New Comparative Grammar of Greek and Latin. Oxford University Press. 1995. 0-19-508345-8.
. Andrew L. Sihler. New Comparative Grammar of Greek and Latin. Oxford University Press. 1995. 0-19-508345-8.
. Donald Ringe . From Proto-Indo-European to Proto-Germanic. Oxford University Press . 2006 . 978-0-19-955229-0.