nan- (prefix) "backwards" (NDAN) or "back", as in nanwen- "return" (go/come back, PE17:166), cf. also nanquernë *"turned back", the pl. form of nanquerna _(VT49:17-18). _Apparently assimilated nal- in nalláma "echo" (if this represents nan-láma "back-sound", sound coming back).
Quenya
quer-
turn
nan-
backwards
#quer- vb. "turn" (transitive), attested as pa.t. quernë (VT49:18-20). Compare kuere (kwere) as one variant of a stem meaning "turn" (PE14:65). English intransitive "to turn" requires a reflexive pronoun in Quenya: mo quernë immo "one turned oneself" (VT49:6), in idiomatic English simply "one turned". Passive participle #querna "turned", isolated from nuquerna (q.v.) "under-turned" = reversed, turned upside down. Also in númenquerna "turned westward" (VT49:18), nanquernë "turned back", pl. form of *nanquerna (VT49:17-18, 20)