Abstract: This paper examines the durability of neologisms in medieval French and beyond, concentrating in particular on words derived from Arabic and transmitted through Latin translations. An examination of the Old French Chirurgie d'Albucasis suggests that a high proportion of the technical terms from Arabic are attested only in that translation. Three of the Latin manuscripts of Albucasis contain proto-glossaries, probably a principal means by which technical loanwords could be transmitted; but these, in fact, are by no means exclusively glossaries to the text, but rather wider-ranging synonyma. A part of one of the manuscripts (British Library, MS. Additional 36617) is transcribed to make the point. The study also looks at the medical Arabicisms still present in the TLF, and those listed in vol. XIX of the FEW, and finds that there are very few. The conclusion is that the existence of (in this case) Arabic loanwords in an Old French translation does not mean that any lasting impact has been made on the lexis of French. Most of the words in the Albucasis translation have disappeared.