2.NounA person who regularly travels between two places.
To and from work and home.
Using public transport.
3.NounTo and from work and home.
4.NounUsing public transport.
5.NounNormally a short form of commuter rail, commuter train or commuter bus; A transport system or a vehicle in such systems used to transport commuters (#2)
"He takes the commuter to headquarters at least once a week."