.TH SPELL 1 
.SH NAME
spell \- find spelling errors
.SH SYNOPSIS
.B spell
[ option ] ...
[ file ] ...
.SH DESCRIPTION
.I spell
looks up words from the named
.I files
(standard input default)
in a public spelling list and in a private list.
Words that occur in neither and are not plausibly derivable
from words in the public list
are placed on the standard output.
.PP
.I spell
ignores most
.I troff,
.I tbl,
.I pic,
and
.IR  eqn (1)
constructions.
It understands these options:
.TP
.B \-b
check British spelling
.TP
.B \-v
print all words not literally in the spelling list, with
derivations
.TP
.B \-x
print, marked with `=',
every stem tried in both stop list and spelling list
.PP
The private list, by default $HOME/lib/spelldict, is arranged
one word per line.
.PP
Pertinent auxiliary files may be specified by
environment variables, indicated below with their
default settings.
Copies of all output
are accumulated in the history file, if it is writable.
The stop list filters out misspellings (e.g. thier=thy\-y+ier)
that would otherwise pass.
.SH FILES
D_SPELL=/usr/dict/hlist[ab]: hashed public lists, American & British
.br
S_SPELL=/usr/dict/hstop: hashed stop list
.br
H_SPELL=/usr/dict/spellhist: history file
.br
A_SPELL=$HOME/lib/spelldict: private list
.br
P_SPELL=/usr/lib/spell: the main routine
.br
deroff(1), sort(1), tee(1), comm(1)
.SH SEE ALSO
dict(7)
.SH BUGS
A malicious opponent can defeat
.I spell's
heuristics for word derivation,
but this rarely happens in practice.
.br
The spelling list's coverage is uneven;
in particular biology, medicine, and chemistry are
covered very lightly.
New installations will probably wish to 
monitor the output for several months to gather
local additions.
.br
British spelling was done by an American.