In the Harry Potter universe, a Muggle-born is a witch or wizard whose mother and father are strictly non-magical.
The Muggle-borns are sometimes treated with disdain by witches and wizards with magical parentage.

Muggle-born: we are just as much part of wizarding society as you pure-bloods.

Pure-blood: who asked you, you filthy, dirty-blood Muggle-born.
by Newmarduk June 27, 2015
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