Literally the track left by a wheel on a road or path. Figuratively, it can refer to a precedent or the path taken by a predecessor, as in 轍を踏む (to repeat a failure).
Deep ruts had formed in the mud.
He was careful not to repeat the mistakes of his predecessors.
Standard kanji form; the reading てつ is rare and mostly found in compounds.
Kana spelling is sometimes used when the kanji is considered difficult or for clarity.
The kanji 轍 is composed of 車 (vehicle) and 徹 (penetrate) abbreviated, suggesting the mark left by a vehicle. The reading わだち is a native Japanese word of uncertain origin.