kill -9

Force-kill a process immediately (SIGKILL)

SIGKILL (9) cannot be caught or ignored; the kernel terminates the process instantly. Use only when a process refuses to respond to SIGTERM. Risk: no chance to flush buffers or release locks.

Example

$ kill -9 4821
(process 4821 killed immediately)

Tip: Type it yourself in the terminal below - reading is not the same as doing.