idyll or U.S. (sometimes) idyl n. 1. a poem or prose work describing an idealized rural life, pastoral scene, etc. 2. a charming or picturesque scene or event. 3. a piece of music with a pastoral character. [C17: from L, from Gk eidullion, from eidos shape, (literary) form] - i'dyllic adj. - i'dyllically adv.