Longman Dictionary of Contemporary English
boat train
noun
EXAMPLES FROM CORPUS
▪ Tomorrow I will go on the boat train with my parents.
Wiktionary
boat train
n. (context UK Ireland travel English) A travel service with a train timed to arrive at a ferry port in time for the onward travel by ferry. (or v.v.)
WordNet
boat train
n. a train taking passengers to or from a port
Wikipedia
Boat train
A boat train is a passenger train operating to a port for the specific purpose of making connection with a passenger ship, such as a ferry or ocean liner. Through ticketing is normally available. __NOTOC__