unhash [ -adfms ] name ...
       Remove  the element named name from an internal hash table.  The
       default is remove elements from the command hash table.  The  -a
       option  causes  unhash to remove regular or global aliases; note
       when removing a global aliases that the argument must be  quoted
       to  prevent  it  from  being expanded before being passed to the
       command.  The -s option causes unhash to remove suffix  aliases.
       The  -f  option causes unhash to remove shell functions.  The -d
       options causes unhash to remove named directories.   If  the  -m
       flag  is  given  the  arguments are taken as patterns (should be
       quoted) and all elements of the corresponding  hash  table  with
       matching names will be removed.

unalias [ -ams ] name ...
       Removes aliases.  This command works  the  same  as  unhash  -a,
       except that the -a option removes all regular or global aliases,
       or with -s all suffix aliases: in this case  no  name  arguments
       may  appear.   The options -m (remove by pattern) and -s without
       -a (remove listed suffix aliases) behave as for unhash -a.  Note
       that the meaning of -a is different between unalias and unhash.

unfunction
       Same as unhash -f.