What does run up mean slang?

: a usually sudden increase in price. : the period immediately before an action or event.

What does it mean to run up on somebody?

run up on (someone or something)

1. To approach someone very quickly, especially with the intent of attacking them.

How do you use run up in a sentence?

I’ll run up and get the box. The houses run up the hillsides. Let me just run up and change. He refused to release her, instead pushing her into a painful run up the beach, over the sandbags, and out of immediate danger.

What does it mean to run up against?

Definition of run up against

: to experience (something difficult) She has run up against a lot of opposition.