いちにちいちにち 一日一日 LinksSentence search for 一日一日Sentence search for いちにちいちにちKanji details for 一 and 日Edit in JMdict Adverb (fukushi), Adverb taking the 'to' particle1. gradually; day by dayNoun2. every day; each dayいちにちいちにち一日一日とさむ寒くなってきた。It is getting colder and colder day by day. Discussions Log in to talk about this word.