The terahertz, abbreviated THz, is a unit of electromagnetic (EM) wave frequency equal to one trillion hertz (1012 Hz). The terahertz is used as an indicator of the frequency of infrared (IR), visible, and ultraviolet (UV) radiation. The terahertz is not commonly used in computer and wireless technology.

one trillion periods per second

A frequency of, or a frequency in the range of a trillion hertz. Abbreviated THz.