寸すん鉄てつ人ひとを刺さす

expression, godan verb (-su)

make a cutting remark; stab with a short blade

Idiomatic expression; the literal meaning is 'to stab someone with a short blade', but it is almost always used figuratively for delivering a sharp, concise criticism or witty remark.

• 彼かれの寸すん鉄てつ人ひとを刺さすような一いち言げんに、会かい場じょうが静しずまり返かえった。

  The room fell silent at his cutting remark.

• 寸すん鉄てつ人ひとを刺さすとは、短みじかい言こと葉ばで相あい手ての急きゅう所しょを突つくことだ。

  'Suntetsu hito wo sasu' means to strike at someone's weak point with a short phrase.