Rethinking Stang’s Law, with a Note on Gk. πóτνια

Stang’s Law (Mayrhofer, 1986: 163–164) is the inner-PIE sound change by which pre-PIE word-final *-Vu̯m(s) and *-VHm(s) gave PIE *-V̄m(s), with subsequent reduction of *-V̄ms to *-V̄s. In his original formulation of the rule (1965), Stang was chiefly concerned with the sequence *-u̯m(s), and specifically with the acc. sg. and pl. forms of the words for ‘sky’ and ‘cow’ (Ved. acc. sg. dyā́m (cf. Gk. Ζῆν), gā́m (cf. Gk. (Dor.) βῶν), acc. pl. gā́ḥ (cf. Gk. (Dor.) βῶς) for theoretically expected *dyávam < *di̯éu̯m̥, *gā́vam < *gwóu̯m̥, *gā́vaḥ < *gwóu̯m̥s). The extension of the rule to *-Hm(s) sequences, as in the ā-stem acc. sg. and pl. in *-ah2m, *-ah2ms (> Ved. -ām, -āḥ; see below), was very much an add-on to Stang’s main discussion, taking up only eight lines. It is this ‘laryngeal’ part of Stang’s Law, which we will call SLH, that will occupy us here.