flag semaphore
手旗信号
Flag signals
Heliograph
International Code of Signals
International maritime signal flags
Railway signalling
Aircraft marshalling
Optical landing system
Semaphore line
Signal lamp
Substitute flag
Traffic guard
https://source.unsplash.com/featured/?flag-semaphore#.png
/suto3/google.iconflag semaphore
/suto3/Google画像検索.iconflag semaphore
/suto3/Google定義検索.icon flag semaphore
/suto3/wikipedia.iconflag semaphore
/suto3/weblio.icon flag semaphore
/suto3/kotobank.icon flag semaphore
/suto3/jisho.icon flag semaphore