Mathematically known as four.
There are tetra angles in this formation.
by SCTetra February 17, 2009
Tetra is the pirate captain in The Legend of Zelda: The Wind Waker. She is princess Zelda although she does not know this at first. She is cold and mean at first but gradually becomes nicer.
Tetra just shot Link out of a cannon while he was asleep.
by Link, of course. February 23, 2013