Bump And Grind Meaning

(by extension) A combination of movements resembling such a dance, as in road racing, whitewater kayaking, or exercising; any activity involving prolonged jarring or shaking.

Example: 1982, Gerald Clarke, "Are the Stars Out Tonight?," Time, 9 Aug.,
  One of the oddest spectacles in America, in fact, has to be a Tom Jones audience, in which a couple of dozen women, usually attractive and well dressed, throw their panties onto the stage and compete for what appears to be a deep kiss from the male master of the bump and grind.
1998, Lloyd Grove and John Harris, "Crisis Quarterback: Gregory Craig Is Calling the Plays On Clinton's Team," Washington Post, 19 Nov., p. D01 (retrieved 7 Aug. 2008),
  "There's inevitably a bump and grind when someone new comes into an established organization," says former senior adviser Rahm Emanuel.
2005, Viv Bernstein, "Victory Gives Kenseth a Shot at the Chase," New York Times, 29 Aug. (retrieved 7 Aug. 2008),
  The typical bump and grind of short-track racing at Bristol Motor Speedway met with the panicked push of the final races of the Nascar Nextel Cup.