win·dow·ful \ˈ ̷ ̷ ̷ ̷ˌfu̇l\noun (pluralwindowfulsalsowindowsful) Etymology:window (I) + -ful : as much or as many as a window will hold or allow to pass through or be visible < let in a whole windowful of light — Commonweal > < a full train … piled with windowfuls of faces — Bruce Marshall >