§ Rath a Chalardain ’Street of the Lampwrights’ (WR:287)
§ Ernil a Pheriannath (ibid.)
The first name is a street in Minas Tirith, later Rath Celerdain (LotRV, ch.1) < rath ’street (in a city)’ from rath- ’climb’ + celerdain, pl. of calardan ’lampwright’ from calar ’a portable lamp’ (RC:523, UT:255, PE17:96). Compare RAT-, KAL-, TAN-.
Ernil i Pheriannath ’Prince of the Halflings’ (Rgeo:75) < ernil ’prince’ (UT:428), probably arn ’royal’ (Let:347) + suffix -il; and periannath, coll. pl. ’the Hobbits (as a race)’ from perian ’halfling’ (cf. PER-) with nasal mutation after the plural article.
In both names the genitive particle an < √ANA/NĀ (PE17:146) is used. It causes nasal mutation to the following words: celerdain > a chelerdain and periannath > a pheriannath. It otherwise appears in an objective role: dagnir an Glaurung ’Slayer of Glaurung = he who slew Glaurung’ (PE17:97), meaning that it is employed where a verb phrase with a direct object (’to slay Glaurung’) becomes a noun phrase. But obviously, an plays no such role in these early forms.
A discussion of the derivatives of √ANA/NĀ mentions that na, before vowels nan with nasal mutation, means ”with” in sense of possessing, provided with, especially of characteristic feature (PE17:147), so i·arben na megil and ’The Knight of the Long Sword’. This could apply to Rath a Chalardain – the lampwrights are a characteristic feature of the street. See also Henlo n’Annun, Hennuil n’Annun above (3.18).
Also notable is calar in the earlier plural calardain, compared to later i-affected celerdain.