spellin [ List | Number ]
The spellin command creates a spelling list for use by the spell command. The parameter for the spellin command can be a file name or a number. The spellin command combines the words from the standard input and the already existing spelling list file and places a new spelling list on the standard output. If no list file is specified, a new list is created. If Number is specified, the spellin command reads the specified number of hash codes from standard input and writes a compressed spelling list.
To add the word hookey to the spelling list named myhlist, enter:
echo hookey | spellin /usr/share/dict/hlista > myhlist
The spell command.