A "harsh critic" is someone who is very critical or judgmental, often being strict and unsympathetic towards something or someone they are reviewing or discussing.
Sentences with «harsh critic»
In our field visits, we heard stories of teachers who were once harsh critics of PL becoming its most vocal advocates. (educationnext.org)
They are harsh critics on themselves and would say they didn't play their best.. (allsportsseries.com)
My taste testers are gluten eaters and are very harsh critics, so the successes are even sweeter. (glutenfreegirl.com)