りがく 理学 Common word LinksSentence search for 理学Sentence search for りがくKanji details for 理 and 学Edit in JMdict Noun1. physical science; natural scienceNoun2. physicsSee also 物理学Noun3. lixue (Song-era Chinese philosophy)Noun4. philosophyArchaic, See also 哲学 Discussions Log in to talk about this word.