gamble

from The American Heritage® Dictionary of the English Language, 5th Edition.

• intransitive verb To bet on an uncertain outcome, as of a contest.
• intransitive verb To play a game of chance for stakes.
• intransitive verb To take a risk in the hope of gaining an advantage or a benefit.
• intransitive verb To engage in reckless or hazardous behavior.
• intransitive verb To put up as a stake in gambling; wager.
• intransitive verb To expose to hazard; risk.
• noun A bet, wager, or other gambling venture.
• noun An act or undertaking of uncertain outcome; a risk.

from The Century Dictionary.

• noun A venture in gambling or as in gambling; a reckless speculation.
• To play at any game of hazard for a stake; risk money or anything of value on the issue of a game of chance, by either playing or betting on the play of others; hence, to engage in financial transactions or speculations dependent for success chiefly upon chance or unknown contingencies: as, to gamble with cards or dice; to gamble in stocks.
• Gambling contract. See contract.
• To lose or squander by gaming: with away or off.
• noun A leg.

from the GNU version of the Collaborative International Dictionary of English.

• noun colloq. An act of gambling; a transaction or proceeding involving gambling; hence, anything involving similar risk or uncertainty.
• transitive verb To lose or squander by gaming; -- usually with away.
• intransitive verb To play or game for money or other stake.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A significant risk, undertaken with a potential gain.
• noun A risky venture
• verb To take a risk, with the potential of a positive outcome.
• verb To play risky games, especially casino games, for monetary gain.
• verb transitive To risk (something) for potential gain.
• verb To interact with equipment at a casino

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• verb play games for money
• noun money that is risked for possible monetary gain
• verb take a risk in the hope of a favorable outcome
• noun a risky act or venture