Roman candle, aid to navigation, alarm, amber light, balefire, beacon, beacon fire, bell, bell buoy, blinker, blue peter, buoy, caution light, flare, fog bell, fog signal, fog whistle, foghorn, glance, go light, gong buoy, green light, heliograph, high sign, international alphabet flag, international numeral pennant, kick, leer, marker beacon, nod, nudge, parachute flare, pilot flag, poke, police whistle, quarantine flag, radio beacon, red flag, red light, rocket, sailing aid, semaphore, semaphore flag, semaphore telegraph, sign, signal, signal beacon, signal bell, signal gong, signal gun, signal lamp, signal light, signal mast, signal post, signal rocket, signal shot, signal siren, signal tower, spar buoy, stop light, stop-and-go light, the nod, the wink, touch, traffic signal, watch fire, white flag, wigwag, wigwag flag, wink, yellow flag

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