a : the speed at which someone or something moves
He can run at a decent pace. [=he can run fairly fast]
We walked at a leisurely pace along the shore.
I told the kids to pick/step up the pace. [=go faster]
b : the speed at which something happens
The pace of the story was slow.
His new album is selling at a blistering/breakneck/dizzying pace.
Despite quickly advancing medical technology, the pace [=(more commonly) rate] of change in her field remained slow and steady.
She liked the fast pace of life in the city. [=she liked the fast way things happened in the city]
2 [count] : a single step or the length of a single step — usually plural
The tree is about 30 paces from the front door.
The dog walked a few paces behind us.