‖ iˈllaunIrish. [ad.Ir.eileán, oileán (prob.ad.ON.eyland, øyland).] An islet. 1882Cornh. Mag. Mar. 321 Tiny illauns and carrigeens, which barely afford a foothold to the passing gull.189519th Cent. Mar. 422 Their curraghs were cast ashore and dashed to pieces against the illaun.