terabyte (unit, data) (TB) A unit of data equal to one trillion bytes. A terabyte is 10^12 bytes or 1000^4 bytes or 1000 gigabytes.
A terabyte is roughly the amount of data in 117 DVDs (at 8.5 gigabytes each). 1000 terabytes are one petabyte. (Note the spelling - one 'r'). See prefix. Last updated: 2013-11-03