1 derailment (railway accident)

2 to leave the rails

3 fig. to overstep bounds

4 fig. to have an extramarital affair

1 store

2 shop

1 a bed (on a train)

2 a couchette

1 locus

2 orbit

3 trajectory

4 track

1 orbit

2 railway or tram line

3 fig. conventional way of thinking

1 lit. hiding the sky and covering the earth (idiom); fig. earth-shattering

2 omnipresent

3 of universal importance

1 extravagance and waste (idiom)