出轨

derailment (railway accident) / to leave the rails / fig. to overstep bounds / fig. to have an extramarital affair

to go out / to come out / to occur / to produce / to go beyond / to rise / to put forth / to happen / (used after a verb to indicate an outward direction or a positive result) / classifier for dramas, plays, operas etc

variant of 出[chu1] (classifier for plays or chapters of classical novels)

course / path / track / rail