- (intransitive, literally) To collide with.
- He bumped into the wall. I guess that's a risk you take when you read while walking.
- (transitive, literally) To cause (a thing) to collide with.
- The roads were so slippery that I couldn't stop, and I bumped my car into the car in front of me.
- (transitive, idiomatic) To meet by chance.
- We bumped into each other at the library yesterday.