The etymology of the name Osiris is highly controversial. In this paper, most proposals are not discussed individually but collectively, according to the suggested derivatives. All the connections with jr.t 'eye' and jr(j) 'to do' are rejected on phonetic or morphological grounds (particularly based on evidence from Meroitic, cuneiform writing, the phonetic development, and the formation of nouns). The most plausible etymology of the remaining is J. Gwyn Griffiths' explanation of Osiris as 'the Mighty One' (*wasuruw). It can be shown that his suggestion is fully in accordance with the requirements of phonetics and derivational morphology. Moreover, the odd writing of the name can be explained as a regular example of the archaic hieroglyphic spelling which was still in vigour one and a half centuries before the first testimony of the name Osiris.