[n] any venturesome undertaking especially one with an uncertain outcome
[n] a commercial undertaking that risks a loss but promises a profit
[n] an investment that is very risky but could yield great profits; "he knew the stock was a speculation when he bought it"
[v] put forward, of a guess; "I am guessing that the price of real estate will rise again"
[v] express in spite of possible refutation
[v] proceed somewhere despite the risk of possible dangers; "We ventured into the world of high-tech and bought a supercomputer"
[v] put at risk; "I will stake my good reputation for this"