kill [-s sigspec | -n signum | -sigspec] pid | jobspec ... or kill -l [sigspec]
Send the processes named by PID (or JOBSPEC) the signal SIGSPEC.
If SIGSPEC is not present, then SIGTERM is assumed. An argument of -l
lists the signal names; if arguments follow -l they are assumed to be
signal numbers for which names should be listed.
Reference: https://cgit.git.savannah.gnu.org/cgit/bash.git/plain/builtins/kill.def?h=bash-5.3