【计】 go-ahead tone
go ahead of the rest; in advance; precession
【计】 anticipated; anticipatory; look-ahead
aspirate; news; sound; tone
【医】 bruit; note; phon-; phono-; sonus; sound; tone
semaphore; signal
【计】 semaphore; signal
【化】 sign; signal
【医】 signal
【经】 call letter; signal