melodiumEtymologyAlternative form of melodeon. Both this word and its variant melodeon are ultimately borrowings from French French mélodium and German German Melodium. Attested from 1846.melodium means A type of reed organ, similar to a harmonium. Lexicurio rates it Sui generis — a strength score of 87 out of 100.nounA type of reed organ, similar to a harmonium.A music hall.