Abstract Essential oils isolated by water distillation were analyzed by GC and GC/MS. In Origanum x majoricum, 74 constituents were identified. The trans-sabinene hydrate and carvacrol were the most prominent compounds, followed by sabinene, Î³-terpinene and terpinen-4-ol. In O. x intercedens and O. x minoanum, 67 and 85 compounds were identified, respectively, with carvacrol predominating (75â80%) in both hybrids. Key Word Index: Origanum x majoricum O. x intercedens O. x minoanum Lamiaceaeessential oil composition trans-sabinene hydratecarvacrol