/usr/bin/look [-d] [-f] [-tc] string [filename]
The look command consults a sorted filename and prints all lines that begin with string.
If no filename is specified, look uses /usr/share/lib/dict/words with collating sequence -df.
look limits the length of a word to search for to 256 characters.
-d Dictionary order. Only letters, digits, TAB and SPACE characters are used in comparisons.
-f Fold case. Upper case letters are not distinguished from lower case in comparisons.
-tc Set termination character. All characters to the right of c in string are ignored.
/usr/share/lib/dict/words spelling list
See attributes(5) for descriptions of the following attributes:
|ATTRIBUTE TYPE||ATTRIBUTE VALUE|
grep(1), sort(1), attributes(5)