one of the wizard swears used in the popular youtube video potter puppet pals in "wizard swears".
used to insult other wizards
or to distract them so you can run away
and to poke fun at the spell expecto patronum used to ward off dementors from azkaban as used in the books and movies
"everyone let's go" *harry to ron and herminone*
"expecto patronads" *runs away from snape*
The shortened form of this word is "nads", but both can be used to the same effect. Originally coined in the famous puppet videos on youtube as a wizard swear, it is now a synonym for the male genitals, better known as balls.
My, what large nads you have!
That man has impressive expecto patronads.