Transmission is the following:

• Generally, transmission is the act of passing something on.
• In mechanics, a transmission is the gear system that transmits mechanical power from an engine via a driveshaft to an axle.
• In communications, transmission is the act of transmitting electrical messages (and the associated phenonomena of radiant energy that pass through mediums).
• In medicine, transmission is the passing of a disease from an infected individual or group to a previously uninfected individual or group.
• In electrical power engineering, transmission delivers generated electricity to consumers.