vehicle

Any inanimate object (as a towel or money or clothing or dishes or books or toys etc.) that can transmit infectious agents from one person to another.

A conveyance that transports people or objects.

A medium for the expression or achievement of something.

“his editorials provided a vehicle for his political views”

“a congregation is a vehicle of group identity”

Any substance that facilitates the use of a drug or pigment or other material that is mixed with it.