Raicu is a Romanian-language of Serbian or Bulgarian origin, related to Rajko; as reported by linguist Alexandru Graur, it is widely assumed to be derived from rai ("heaven", hence "heavenly"), but is more likely a derivative of the given name "Radu". It is also occasionally present as a given name, as with the literary and social critic Raicu Ionescu-Rion (1872âÂÂ1895).