1. past tense of niff; to smell bad or emit an unpleasant odor
Usage: informal; chiefly British

Examples

• The old gym bag niffed after sitting in the locker for weeks.
• His socks niffed so badly that everyone left the room.
• The kitchen niffed of burnt toast this morning.
• That cheese niffed when we opened the package.
• The locker room niffed terribly after practice.