defunc process 🔗 link

Hi all!

One of my hobbit client just turned purple. Then I notice that there is a <defunc> process running with hobbit. What does it mean?
It is installed in a Solaris 5.7. Please help

jupiter% ps -l -u hobbit
 F S   UID   PID  PPID  C PRI NI     ADDR     SZ    WCHAN TTY      TIME CMD
 8 S   204 18691 18680  0  41 20        ?    171        ? pts/5    0:00 csh
 8 Z   204 23486 23485  0   0                                      0:01 <defunct>
 8 S   204 23485     1  0  41 20        ?    122        ? ?        0:00 hobbitla
jupiter%

Thanks and regards,
Ryan