忽 こつ Meanings Number one hundred-thousandth Adverb sudden; abrupt; unexpected (usu. 忽として) See also: 忽然 (こつぜん). Kanji 忽 in a moment; instantly; all of a sudden. Read as コツ. Example sentences コツ、知ってるよ。I know the ropes. Words containing 忽 忽然 (こつぜん) sudden 粗忽者 (そこつもの) careless person 忽焉 (こつえん) sudden And 2 more. Jinuma: Japanese Dictionary · Word lists