Essential oil yield of Origanum onites from Chios (3–7%) among the highest reported.
Carvacrol content of O. onites oil from Chios (69–93%) among the highest reported.
O. onites oil composition/yield not related to different habitats on Chios.
O. onites distinguished from O. vulgare subsp. hirtum based on oil components.
Wild O. onites from Chios: natural capital with high potential for industrial use.