Толковый словарь английского языка - diffuser

noun Date: circa 1679 one that diffuses: as, a device (as a reflector) for distributing the light of a lamp evenly, a screen (as of cloth or frosted glass) for softening lighting (as in photography), a device (as slats at different angles) for deflecting air from an outlet in various directions, a device for reducing the velocity and increasing the static pressure of a fluid passing through a system