1.
to enter a building by force; to open a car, etc. by force :
We had our car broken into last week.
—related noun break-in
2.
to begin laughing, singing, etc. suddenly :
As the President's car drew up, the crowd broke into loud applause.
3.
to suddenly start running; to start running faster than before :
He broke into a run when he saw the police.
Her horse broke into a trot.
4.
( BrE ) to use a banknote of high value to buy sth that costs less :
I had to break into a £20 to pay the bus fare.
5.
to open and use sth that has been kept for an emergency :
They had to break into the emergency food supplies.
6.
to be successful when you get involved in sth :
The company is having difficulty breaking into new markets.