As a noun, a tune is a simple melody you can hum or sing. As a verb, to tune means to adjust an instrument or device so it works or sounds correct.
From Middle English "tune" or "toun" meaning sound or tone, from Old French "ton" and Latin "tonus" for sound or pitch. It originally referred more generally to musical sound before narrowing to recognizable melodies.
The word "tune" is closely related to "tone"—they’re basically sound cousins that split jobs: tone is about quality of sound, tune is about a pattern you remember. When you say someone is "in tune" with something, you’re secretly using a musical metaphor for fitting perfectly with a situation.
Complete word intelligence in one call. Free tier — 50 lookups/day.