From Greek 'melos' (song, originally 'limb') + 'aoide' (singing) — a melody was an articulated member of music.
A sequence of single notes that is musically satisfying; a tune; the principal part in harmonized music.
From Old French 'melodie,' from Late Latin 'melodia,' from Greek 'melōidía' (μελῳδία, singing, chanting, a choral song, lyric poetry set to music), formed from 'mélos' (μέλος, a song, a musical phrase, a limb, a member of the body) and 'aoidḗ' (ᾠδή, a song, from 'aeídō,' I sing). The compound is semantic and structural: 'mélos' originally meant a 'limb' or 'member' — a melody was conceived as an articulated 'part' or 'limb' of a larger musical structure, just as a limb is part of a body. This anatomical metaphor for musical structure is significant
The word 'melodrama' literally means 'song-drama' — from Greek 'mélos' (song) and 'drâma' (action, play). It originally described a form of theater in which the dialogue was accompanied by orchestral music. The negative connotation of exaggerated emotion came later, in the nineteenth century.