Old English gold, from Proto-Germanic *gulth- (cf. Old Saxon, Old Frisian, Old High German gold, German Gold, Middle Dutch gout, Dutch goud, Old Norse gull, Danish guld, Gothic gulþ), from PIE root *ghel- "yellow, green," possibly ultimately "bright" (cf. Old Church Slavonic zlato, Russian zoloto, Sanskrit hiranyam, Old Persian daraniya-, Avestan zaranya- "gold;" see Chloe).
As an adjective from c.1200. In reference to the color of the metal, it is recorded from c.1400.