an inactive process that is deleted at some later time when its parent process executes wait or waitpid
a process that has exited, but whose exit code has not reached its parent process
a process that occupies a slot in the process table, but has no other space allocated to it either in user or kernel space
a process that only occupies an entry in the process list
a term in computing for a process that exists but which has completed execution
An ended process whose entry remains in the process table, but to which a user or kernel space is not allocated. A process becomes a zombie process when it issues the exit subroutine and the following circumstances occur: Its parent process is not running a wait subroutine and has not set its SIGCLD signal action to the SIG_IGN value indicating that it does not intend to wait for its children to finish.
On Unix operating systems, a zombie process or defunct process is a process that has completed execution but still has an entry in the process table, allowing the process that started it to read its exit status. The term zombie process derives from the common definition of zombie—an undead person. In the term's colorful metaphor, the child process has died but has not yet been reaped.
