こ との粉 LinksSentence search for との粉Sentence search for とのこSentence search for 砥の粉Sentence search for 砥粉Kanji details for 粉Edit in JMdict Noun1. tonoko; powder made from dried clay used as a polishing powder, filler material, etc.Other forms砥の粉 【とのこ】、砥粉 【とのこ】 Discussions Log in to talk about this word.