An expression of anger/rage/evilness/possible indigestion. The catchphrase of a one Lord Voldemort.
What he says when he is

1) pissed off
2) killing someone
3) failing to kill Harry Potter
4) casting a spell
5) falling off a tower at Hogwarts
6) being generally evil
7) has constipation/indigestion
8) pretty much whenever he opens his mouth.
1) Neville: *lops off Nagini's head with sword of Gryffindor like a freaking BOSS*
Voldemort: *very pissed off* Nyeaaaaaaaah!

2) Random Death Eater: My Lord, Hogsmeade Library has owled to say that you are overdue in returning "The Handbook for Evil Overlords: Making it without a Nose" by Steve the Fourth-
Voldemort: Nyeaaaaaaaah! *kills Death Eater*

3) Voldemort: *tries to kill Harry* *fails AGAIN* Nyeaaaaaaaah!

4) Voldemort: *casts spell* Nyeaaaaaaaah!

5) Harry: Let's end this how we started it, Tom. Together!
Voldemort: *falls off tower* Nyeaaaaaaaah!

6) Voldemort: *drives around town sticking babies on pikes* Nyeaaaaaaaah!

7) Random Death Eater #2: My Lord, I did warn that it may not have been wise to eat an entire pumpkin pie, three jars of Cockroach Clusters and drink six bottles of Firewhiskey before attempting to fly around as a cloud of smoke.
Voldemort: *very uncomfortable* Nyeaaaaaaaah!

8) Snape: ....and that is why we believe that using a giant trampoline to bounce Death Eaters over Hogwart's defences would be far more effective than last week's effort, a giant slide. What do you think, my Lord?
Voldemort: Nyeaaaaaaaah!
by TheWuzzy July 23, 2011
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