Yeah... that's not what META means. It's a word of greek origin, not an English acronym. It's a prefix which indicates transcendence or comprehensiveness. Therefore metagaming means playing or understanding the game beyond the scopes of the game itself, such as competitively.
Sources:
The easy one - https://en.wikipedia.org/wiki/Meta
The scholarly one - http://www.perseus.tufts.edu/hopper/text?doc=Perseus%3Atext%3A1999.04.0057%3Aentry%3Dmeta%2F
Fun fact! Aristotle actually used the prefix himself (or perhaps his students did) when writing his sequel to his works "physics". The book was labeled "metaphysics".