cadence

Borrowed from Middle French cadence, from Old Italian cadenza ("conclusion of a phrase of music"), from Latin *cadentia, literally "a falling," a form of cadēns, present participle of cadō, "to fall, to cease." That Latin verb descends from Proto-Italic *kadō, ultimately from Proto-Indo-European *ḱad-e-, "to fall."

The word began as a way to describe a musical phrase falling to its close, and that sense of a falling rhythm carried into English as the general word for rhythmic flow.

Cadence is a doublet of cadenza, the musical flourish, and of chance — both tracing back to that same Latin idea of falling.