Where does the term rookie come from?

The word “rookie” may have originated as a corruption of the word “recruit”, and was originally used in the Army to describe a young soldier or fresh recruit. Other theories suggest that the term could have come from the word “rook”, the chess piece often used last once a game starts; or it could be a play on an old slang word “rook”, which means to cheat, which was applied to young soldiers who would be easily cheated by conmen.