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 filesystem.” Never used for accidental deletion; contrast blow away.
2. Syn. 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 session file?” “Nuke it.”
3. Used of processes as well as files; nuke is a frequent verbal alias for kill -9 on Unix.
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.