Learn in the textbookAdvancement of Mobile Communications and Device Technology
DefinitionTethering (テザリング) shares the mobile phone line (携帯電話回線) of a smartphone or similar device with other equipment such as a PC, connecting it to the internet.
ExplanationBecause the smartphone acts as the relay, a PC can get online while you are out without any dedicated hardware. The two can be linked by, for example, wireless LAN, a USB cable, or Bluetooth.
Memory hookThe English word "tether" means to tie with a rope, which fits the image of a device hitched to a smartphone and led along.