The rhythm at which something recurs. A cadence tuned to what is actually ready is a lighthouse; one tuned to reach is a demand.
Latin cadentia (a falling), from cadere (to fall), by way of Italian cadenza; the word for a musical close and the word for a repeated rhythm both come from the image of a phrase 'falling' to its rest.
The rhythm at which something recurs — set by what is actually ready, this word names a lighthouse; set only by reach, it names a demand.