the.com/tune

A melody you can hum badly and still be understood.

means A sequence of musical notes that forms a recognizable melody, or the act of adjusting something to the right pitch or setting.

from Tune comes from Middle English 'tune,' a variant of 'tone,' which traces back through Old French 'ton' to Latin 'tonus,' meaning a sound or stretching (as of a string). The sense split off from 'tone' around the late medieval period, narrowing to mean a melody specifically, while 'tone' kept the broader meaning of sound or pitch. The 'adjusting' sense — as in tuning an instrument or tuning out — grew naturally from the idea of getting the pitch, and eventually the whole setup, exactly right.

etymology
variant of tone, split off meaning in 14th century
instinct test
humans recognize a tune after 3-5 notes
idiom use
to tune is to fine-adjust, not just sing
earworm effect
catchy tunes loop involuntarily for days
the.com · every word