Which means, Vehicle-to-vehicle. This is an automobile technology that was designed to allow Cars and other road vehicles, to "talk" to each other. The systems currently work on the 5.9 GHz band, set aside by the United States Congress in 1999, which is also the unlicensed frequency used by WiFi. The US V2V standard is also commonly known as WAVE, which means, Wireless Access for Vehicular Environments. This is based on the standard IEEE 802.11p.
See also V2X