八達通

Octopus card (Hong Kong smart card for electronic payments)

eight; 8

surname Da

to attain / to reach / to amount to / to communicate / eminent

to go through / to know well / (suffix) expert / to connect / to communicate / open / to clear / classifier for letters, telegrams, phone calls etc

classifier for an activity, taken in its entirety (tirade of abuse, stint of music playing, bout of drinking etc)