Symbol, Sign, Stopsign, Outdoor, attention, background, blank, blue, color, copyspace, detail, forefront, halt, information, message, metal, nobody, object, octagon, prohibition, red, road, roadsign, safety, sign, signal, signs, single, sky, stop, stopsign, symbol, text, traffic, transport, transportation, warning, white, outdoor, diaphragm, commoner, one, law, character, outside, mechanism, writing, 1, unity, crimson, document, subject matter, cipher, ace, ending, informing, person, vanguard, route