What is "runs up against"

Usage examples of "runs up against".

At least the studio was in a part of London where a lot of the best voice-over studios were, north of Oxford Street in the garment district which spreads east from Regent Street for a couple of blocks till it runs up against the straggle of the Middlesex Hospital's many outstations of sickness.

Then the growth will expand until it runs up against its property lines.

Which was how, after first stopping by Jack's school bus, he found himself on the grounds of Butler University, down where the common runs up against the riverbank, saying hello to Jack and Katy.

But even if there are mammal species for which male lactation would be advantageous, its realization runs up against problems posed by the phenomenon termed evolutionary commitment.

He's been boasting around town that if he ever runs up against me, he's going to show just how smart he is.

Then he runs up against a dog on the loose and gets mauled - or killed.