A main road or highway, especially in ancient Rome. (Mainly used in set phrases, below.)
A vertical opening that is filled with a conducting material, such as metal to allow for the electrical connection of several layers on the IC, typically either tungston or Cu
A small hole in a printed-circuit board filled with metal which connects two or more layers
If you go somewhere via a particular place, you go through that place on the way to your destination. Mr Baker will return home via Britain and France
If you do something via a particular means or person, you do it by making use of that means or person. Translators can now work from home, via electronic mail systems