From Longman Dictionary of Contemporary Englishlockjawlock‧jaw /ˈlɒkdʒɔː $ ˈlɑːkdʒɒː/ noun [uncountable] informal MItetanus
Examples from the Corpus
lockjaw• He's trying so hard to force his teeth through that wodge of food he's in danger of developing lockjaw.• They haven't stopped smiling for at least two decades, which suggests an extremely bad case of lockjaw. 