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1 definition by Fuctard

When someone takes a sexual innuendo so far as to make in uncomfortable for the others participating in the good times, and ultimately embarrassing themselves due to lack of social grace. The b-line is also crossed when recounting situations and to much detail is given on some of the more personal parts of the story.
"Brad crosses the b-line when he talks about fire crotches"
"You crossed the b-line with that one."
by Fuctard June 21, 2006