Refers to a regularly traveled route or path, often implying a habitual or repeated journey. Can be used for physical roads or metaphorical paths.
He takes the same route to work every day.
This road was once a route for merchants.
Compound of 通い (kayoi, 'going back and forth', the continuative form of 通う kayou) and 路 (ji, 'road, path'). The exact historical derivation is uncertain, but the word has been used since classical Japanese to mean a regularly traveled route.