Comments:ЭСТЯ 1, 301. The root is attested late and may be theoretically derived from *Erin 'lip' (v. sub *i̯ằré); however, the latter can also mean 'edge (of a dish)' in some languages and one can suspect that PT actually merged *Erin 'lip' and *Erin 'edge', while the form *Erneg was derived only from the latter.