Bakugan: Bakugans are transforming marbles that turn into incredible creatures once you throw them to the battlefield. They are creatures from an alternate dimension called Vestroia. Bakugan is also a Japanese word that means "exploding sphere."
Gate Card: Gate Cards are the playing surface used for the Bakugan game. The Gate Cards contain a magnetic plate which triggers the Bakugan rolled onto them to open ("Stand").
Ability Card: An Ability Card is an extremely valuable card to be holding in a deck. They are played from the hand at certain times to affect the outcome of the match. It's also quite forceful and when used properly can have a devastating effect on your opponents.
Attribute: The attribute of Bakugan is representative of the element of the Bakugan; Fire (Pyrus), Light (Haos), Water (Aquos), Darkness (Darkus), Wind (Ventus) and Earth (Subterra).
G-Power: G-Power (G) is the basic measure of power of a Bakugan. It may be affected by Ability Cards, Gate Cards, etc.
Evolution: After a Bakugan battles enough than it has the power to become an Evolved Bakugan. These Bakugan keep their original attribute (although in some cases they gain one) but they gain higher G-Power and slight appearance difference.
Support Weapon: Support Weapons are a Special Weapon/Support Piece. They come in many different shapes but are not round like regular Bakugan. They usually grant it a powerful effect of its own.