1. To be beset by; SYN. encounter.
2. To collide violently with an obstacle; SYN. bump into, jar against, butt against, knock against.
When you are driving and hit another vehicle or something near the road, such as a tree or a telephone pole, you run into it.
When you meet people unexpectedly or unintentionally, you run into them. Bump into is the same as run into.
When you unexpectedly encounter difficulties or problems, you run into them.
When the total of something grows to a large amount or number, it runs into that amount or number