Medical language, as many technical languages, is rich with morphologically complex words, many of which take their roots in Greek and Latin—in which case they are called neo-classical compounds . Morphosemantic analysis can help generate definitions of such words. This paper reports work on the adaptation of a morphosemantic analyzer dedicated to French (DériF) to analyze English medical neoclassical com-pounds. It presents the principles of this transposition and its current performance. The analyzer was tested on a set of 1,299 compounds extracted from the WHO-ART terminology. 859 could be decomposed and defined, 675 of which success-fully. An advantage of this process is that complex linguistic analyses designed for French could be successfully trans-ferred to the analysis of English medical neoclassical com-pounds. Moreover, the resulting system can produce more complete analyses of English medical compounds than exist-ing ones, including a hierarchical decomposition and seman-tic gloss of each word