wigwag
Wave flags back-forth
Wigwag means to signal by waving flags, lights, or arms in a specific pattern, typically back and forth.
Railroad wigwag signals swing side to side to warn of approaching trains.
The word also serves as a noun for such a signal or the act of signaling: The crossing guard gave a wigwag to stop traffic.
The reduplicative form suggests the repeated back-and-forth motion.
Flag-based signaling system
- flagsSymbolic national cloths
- flaggingLosing vigor progressively
- lanternEnclosed portable light
- torchHandheld burning light source
beacon · mirror · flare · pennant · banner · ensign · bunting · handkerchief
semaphore
Flag-based signaling system
torch · beacon · mirror · flare · pennant · banner · ensign · bunting · handkerchief · helio
swing
Suspended recreational seat
wobble · wave · wag · waggle · oscillate · undulate · rock · bob · jiggle · shake
warning
Alert about danger
hazard · beacon · indicator · railroad · crossing · emergency · flash · blink · strobe
- signalingsmoke signals, flag signals, semaphore, heliograph, Morse code
- railroad crossing partscrossbuck, flashing lights, bells, arms, barriers
- visual signalsflag signals, flag code, hand signals, heliograph
- lampworkingflamework, lampwork, torch, mandrel, glass beads
- nautical signalsgolf flag, semaphore, substitutes, flag signals, distress signals
- railroad slanghogger, highball, gandy dancer, boomer, crummy