1. n. For processor storage, real and virtual storage, and channel volume, 240 or 1 099 511 627 776 bits. 2. n. For disk storage capacity and communications volume, 1 000 000 000 000 bits.
a unit of information or computer storage, commonly abbreviated "tb"
Approximately 1 trillion bits. More exactly, it is 2^40, or 1,099,511,627,776, bits.