To meet someone or something as an opponent or obstruction: We were doing fine until we ran up against those real scumbags (1821+)
But the belief in ascent on the basis of merit alone began to run up against new realities.
His masses of troops had also run up against seemingly unbreakable defenses.
As happy as he and his wife are to be living in Paris, they run up against a predictable array of everyday bureaucratic troubles.
Delve deeper and you run up against the social profanity that was lynching.
Health Hint: To cure a sluggish disposition, run up against a real prize fighter.
"Here I run up against the mysterious again," he complained.
And—it's this kind of folk that the Germans have run up against.
Honest fellows, like you and me, run up against it and get taken in.
Something of a surprise to run up against you suddenly, like this.
And in an eon of lying they never have run up against a short-circuit like that.