tumble across (something)

tumble across (something)

1. Literally, to trip on something with one's foot. I wasn't watching where I was going and tumbled across the root of a tree. The child tumbled across the steps of the house.
2. To find, discover, or happen upon something casually or by chance. I tumbled across this fantastic little café the other day. Let me know if you tumble across my keys—I haven't been able to find them.
See also: across, tumble