Abstract Analysis by GC and GC/MS of the oil of Origanum dayi grown in France from seeds collected from the desert of Judea in Israel, isolated by water distillation, led to the identifcation of 68 constituents. The oil was characterized by high proportions of 1,8-cineole (18.2â26.8%), terpinen-4-ol (16.1â21.6%) and Î±-terpineol (12.9â16.8%). Key Word Index: Origanum dayi Lamiaceaeessential oil composition1,8-cineoleterpinen-4-olÎ±-terpineol