1 [intransitive and transitive] formalTT
to get on a bus, plane, train etc in order to travel somewhere:
The couple boarded the train for New York.
Passengers were standing on the dock, waiting to board.
if a plane or ship is boarding, passengers are getting onto it:
Olympic Airways Flight 172 to Istanbul is now boarding at Gate No. 37.
3 [intransitive always + adverb/preposition]DH
to stay in a room in someone's house that you pay for:
Several students boarded with Mrs. Smith.
to stay at a school at night as well as during the day:
Dickie was sent away to school as soon as he was old enough to board.
board something ↔ outphrasal verb
to pay money and arrange for an animal to stay somewhere
board something ↔ upphrasal verb
The shop was boarded up.