Gimilkhâd's dates of birth and death are given explicitly in the detailed Line of Elros in Unfinished Tales, and those dates give a lifetime of 199 years. The Akallabêth, meanwhile, does not give dates, but says that Gimilkhâd '...died two years before his two hundredth year...'. This latter source must be counting Gimilkhâd's first year as II 3045 (that is, the year of his first birthday), so his 'two hundredth year' by this method would be II 3245.

We can only translate half of Gimilkhâd's name. In volume 9 of The History of Middle-earth, the linguistic notes in The Drowning of Anadûnê provide a detailed discussion of the Adûnaic word gimli, meaning 'star'. Among the plural forms given there is the collective gimil, 'the stars' (that is, all the stars in the sky). So, we can translate the Gimil- element of the name with some confidence, but unfortunately -khâd is not explained in that source or any other, and remains entirely obscure.