In "Ode to the West Wind," poet Percy Bysshe Shelley called the "wild West Wind" the "breath of Autumn's being." But according to Greco-Roman tradition, the west wind was warm and usually gentle. Its Latin name, Favonius, is the basis for the English adjective "favonian" and derives from roots that are akin to the Latin fovēre, meaning "to warm." "Zephyros," a Greek name for the west wind, is the ultimate source of zephyr, meaning "a gentle breeze." In Greco-Roman tradition, it was the north wind, Boreas (aka Aquilo), who was the rude and blustery type.