Wiktionary
roughen up
vb. (context idiomatic transitive English) to make something rough or rougher
Usage examples of "roughen up".
There was a heavy cloud-bank off to the north-west, thick as clotted cream, but Dan Bass had estimated that there would be two or three hours' diving time before the weather began to roughen up.
The benefit of this was to roughen up the edges of their word-perfect pronunciations and ground them in regional colloquialisms so that they didn't sound like a bunch of homogenous Euro-twats.