slip carriage vs slip coach

slip carriage and slip coach both are nouns.

Word	Noun	Adjective	Verb	Adverb
slip carriage	Yes	No	No	No
slip coach	Yes	No	No	No

As nouns, slip carriage and slip coach are synonyms defined as:

slip carriage and slip coach: a railway car at the end of the train; it can be detached without stopping the train

slip carriage (noun)	slip coach (noun)
a railway car at the end of the train; it can be detached without stopping the train	a railway car at the end of the train; it can be detached without stopping the train