/n[y]ook/ 1. To intentionally delete the entire contents of a given directory or storage volume. "On Unix, "rm -r /usr" will nuke everything in the usr file system." Never used for accidental deletion.
2. Synonym for dike, applied to smaller things such as files, features, or code sections. Often used to express a final verdict. "What do you want me to do with that 80-meg wallpaper file?" "Nuke it."
4. On IBM PCs, a bug that results in fandango on core can trash the operating system, including the FAT (the in-core copy of the disk block chaining information). This can utterly scramble attached disks, which are then said to have been "nuked". This term is also used of analogous lossages on Macintoshes and other micros without memory protection.