present participle. Showing a whole lotta ass.
Real citation: “Like headliner Iggy Pop. Shirtless in plumber’s-crack-defying jeans, he never stopped flailing as his Stooges launched into the Bo Diddley shuffle beat of “1969.”
(Doug Brod, “Little Steven’s International Underground Garage Festival,” Spin, Oct. 2004)
Made-up citation: "Now that the plumber’s-crack-defying look passes for normal, and ass cleavage is here to stay, what could the next trend possibly be? Crotch cleavage?"