unhash [ -adfms ] name ...
       Remove the element named name from an internal hash table.  The  de-
       fault is remove elements from the command hash table.  The -a option
       causes  unhash to remove regular or global aliases; note when remov-
       ing a global aliases that the argument must be quoted to prevent  it
       from  being expanded before being passed to the command.  The -s op-
       tion 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  corre-
       sponding 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 suf-
       fix  aliases)  behave as for unhash -a.  Note that the meaning of -a
       is different between unalias and unhash.

unfunction
       Same as unhash -f.
