The law governs the word-final sequences of a vowel, followed by a semivowel (*y or *w) or a laryngeal (*h₁, *h₂ or *h₃), followed by a nasal.
According to the law these sequences are simplified such that laryngeals and semivowels are dropped, with compensatory lengthening of a preceding vowel.
This rule is usually cited in more restricted form as: *Vwm > *Vːm and *Vh₂m > *Vːm (*V denoting a vowel and *Vː a long vowel).
Often the rules *Vmm > *Vːm and also *Vyi > *Vːy are added:[1] This phonology article is a stub.
You can help Wikipedia by expanding it.This Indo-European languages-related article is a stub.