The phrase "powerful wizard" refers to a person who has exceptional magical abilities and is very skilled in using them.
Sentences with «powerful wizard»
It boasts gorgeous vivid particle effects that make you feel like a very powerful wizard. (vrgamesfor.com)
Upon his 11th birthday, Harry Potter (Daniel Radcliffe), who lives in misery with an aunt and uncle that don't want him, learns from a giant named Hagrid (Robbie Coltrane) that he is the orphaned son of powerful wizards. (rottentomatoes.com)
I'm thinking it's probably made by powerful wizards at Hogwarts (but this is just an, albeit awesome, theory). (romper.com)