from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Alternative spelling of labialization.
Sorry, no etymologies found.
The most common assumption is, that they represent different types of consonants, by labialisation example: LinAB *04=TE *87=TWE.
The 'lost puppy' effect of the labialisation really only seems to have had effect on Latin and Greek.
But instead of the *u leaving behind labialisation, the *i and *e left behind palatalisation.