vt. 1. To set to 0. Usually said of small pieces of data, such as bits or words (esp. in the construction 'zero out').
2. To erase; to discard all data from. Said of disks and directories, where 'zeroing' need not involve actually writing zeroes throughout the area being zeroed. One may speak of something being 'logically zeroed' rather than being 'physically zeroed'.