Argonui

noun. royal valour

ar (prefix “high, noble, royal”) + caun (“valor”) + ui (adjectival suffix)

argonui

masculine name. Argonui

The 8th chieftain of the Dúnedain (LotR/1038). The initial element of his name is the prefix ar(a)- “noble”. The remainder of the name might be the noun caun (in any of its various meaning) with the adjectival suffix -ui (as suggested by David Salo, GS/246, 342).

Elements

Word	Gloss
ar(a)-	“noble, royal, high”
caun	“prince, chief, head”
-ui	“-ful, having quality, adjective suffix; possibility, suitability [as verbal suffix], *-able”