# Negative searches

I think a useful feature would be negative searches: searches in which at least one term is constrained to not occur (but no more than all but one terms, of course -- you wouldn't want to bring back all/almost all questions).

This would be useful both for bare terms

prime -ideal


and tags

diophantine -[elementary-number-theory]

• Have you tried it? For me, searching "prime -ideal" works as expected! – Hendrik Vogt Sep 11 '11 at 7:30
• FWIW, Google also recognizes search operators like -. So something like site:math.stackexchange.com +prime -ideal works nicely if the built-in search is not to your taste. – J. M. is a poor mathematician Sep 11 '11 at 9:39