: find relevant definition of term in dictionary or XBNF grammar
if [ $# -eq 0 ]
then
	echo Select a language: ; ls /u/faculty/dick/cs320
	/bin/echo which"? " "\c"; read language
	echo Tap CTRL/C to exit...
	/bin/echo define what"? " "\c"
	while read word
	do	/u/faculty/dick/bin/define "$language" "$word"
		/bin/echo define what"? " "\c"
	done
	exit
elif [ $# -eq 1 ]
then
	dir=.
	word=$1
elif [ $# -eq 2 ]
then
	dir=/u/faculty/dick/cs320/$1
	word=$2

else
	echo "Usage: define [[language] word]"
	exit 1
fi
if expr x$word : 'x....*' >/dev/null
then
	errors=1
else
	errors=0
fi
if expr $PWD : '.*maths$' >/dev/null
then
	file="[a-qs-z]*.mth"
else
if [ -r $dir.syntax ]
then
files=`/u/faculty/dick/bin/seealso $dir.syntax`" /u/faculty/dick/cs320/glossary"
else
files="/dev/null  /u/faculty/dick/cs320/glossary"
fi

fi
tmp=/tmp/def$$  # introduced because of possible bug in agrep RJB Oct1993
/u/faculty/dick/bin/agrep -$errors -wik $word $files >$tmp
/u/faculty/dick/bin/agrep -$errors -i "$word<[^:]*::>" <$tmp|sed 's/^\/u\/faculty\/dick\///
s/^\([^:]*\):\(.*\)$/\2 --\[\1\]/
s/^[    ]*//
s/[     ][      ]*/ /'|/u/faculty/dick/bin/brt 78
rm $tmp
echo \($word\)