The Adûnaic language that underlies Ar-Gimilzôr's name is not well documented, but we have enough circumstantial evidence to form an educated guess in this particular case. The prefix Ar, for example, certainly means 'King', as did the ElvishTar used by earlier Kings of Númenor. The word gimil appears in a linguistic discussion in volume IX of The History of Middle-earth, and there it is interpreted as 'stars'. The -zôr ending is less clear, but by comparison with other Adûnaic names it seems to mean 'fire'. This interpretation fits fairly well, though not perfectly, with the Elvish form of Ar-Gimilzôr's name, Tar-Telemnar, where Telemnar seems to mean 'fire of heaven'.