pilot flag

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noun Nautical.

the flag symbolizing the letter G in the International Code of Signals, flown by itself to request a pilot from a pilot service: a flag of three yellow and three blue vertical stripes.
the flag symbolizing the letter H in the International Code of Signals, flown by itself to indicate that a pilot is on board: a flag with one white and one red vertical stripe.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

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