The Unified Medical Dictionary (UMD) is an English/Arabic Medical Dictionary, which was originally compiled in the late 1960s/early 1970s on the recommendation of and as a result of an initiative by the Arab Medical Union. Later on, the Council of the Arab Ministers of Health asked WHO/EMRO to update and supplement the first edition. A specialized Committee of experts was set up with Dr. M.H. Khayat as the rapporteur to further verify and enrich the first edition. Consequently, two further editions were issued, the last of which (1983) includes French terms.