齿孔 Traditional form: 齒孔 Pinyin (reading): chǐkǒng Definitions: perforations (on a postage stamp) Characters: 齿 - teeth; gears, cogs; age 孔 - opening, hole, orifice; great Traditional characters: 齒 - teeth; gears, cogs; age 孔 - opening, hole, orifice; great