One who plays at a game of chance, who gambles.(noun)
One who takes risks.(noun)
Wiktionary.org : Text is available under the Creative Commons Attribution-ShareAlike License
Use "gambler" in a sentence
"Bush the gambler is betting that he will come out looking like President Reagan, whose deficits bought economic reforms and a stronger national defense."
"But he also is one of the biggest gambles as he is a classic high-risk, high-return sort of riverboat gambler from the back end."
"Where's that little pale printer's devil, the one they call the gambler's ghost?"