The Collaborative International Dictionary of English v.0.48:
Doubling \Dou"bling\, n.
1. The act of one that doubles; a making double;
reduplication; also, that which is doubled.
2. A turning and winding; as, the doubling of a hunted hare;
shift; trick; artifice. --Dryden.
3. (Her.) The lining of the mantle borne about the shield or
4. The process of redistilling spirits, to improve the
strength and flavor.
5. raising the stakes in a game, such as a card game or
backgammon, by a factor of 2.
Doubling a cape, promontory, etc. (Naut.), sailing around
or passing beyond a cape, promontory, etc.