Rachel Uchitel -- Secretly Marries Boyfriend

Rachel Uchitel is off the market ... TMZ has learned she got hitched over the weekend.

We've obtained documents from Clark County, Nevada, showing Rachel and Matt Hahn got a marriage license Sunday night and filed it with the court the next day at 8:58 AM.

Matt was a football player at Penn State and is now a businessman in San Francisco. The two have been living together in San Fran for several months. Matt is 26. Rachel says she's 36.

Rachel -- famous for her fling with Tiger Woods and a $10 million settlement -- was married in 2004 but it only lasted a year and 4 months.