歯し牙がにもかけない

expression, i-adjective

not worth considering; pay no attention to; ignore completely

Idiomatic expression meaning to treat something as utterly insignificant, not even worth a glance. Often used in negative form ～ない. Literally 'not even put on one's teeth', implying something is so trivial it doesn't merit a reaction.

• 彼かれは他た人にんの批ひ判はんなど歯し牙がにもかけない。

  He pays no attention whatsoever to other people's criticism.

• そんな小ちいさな問もん題だいは歯し牙がにもかけずに先さきに進すすもう。

  Let's move on without giving such a trivial problem a second thought.