means of commuting; way of getting to work
Refers to the transportation method used for commuting, such as train, bus, bicycle, or car. Often used when discussing options or changes in commuting.
See also: 足
My new workplace is far, so I use the train as my means of commuting.
After moving, my way of getting to work changed from bus to bicycle.
Compound of 通勤 (commuting) + の (possessive particle) + 足 (foot; here metaphorically 'means of transportation'). The use of 足 for transportation is a common extension.