grille

(noun) small opening (like a window in a door) through which business can be transacted. Synonyms: wicket, lattice.

(noun) grating that admits cooling air to car's radiator. Synonyms: radiator grille.

(noun) a framework of metal bars used as a partition or a grate. Synonyms: grill, grillwork. Example: "He cooked hamburgers on the grill."