通航

通航	tōng háng	connected by air, sea traffic or service
通	tōng	to go through / to know well / (suffix) expert / to connect / to communicate / open / to clear / classifier for letters, telegrams, phone calls etc
通	tòng	classifier for an activity, taken in its entirety (tirade of abuse, stint of music playing, bout of drinking etc)
航	háng	boat / ship / craft / to navigate / to sail / to fly