1) In literal terms: when the runner, in baseball, reaches second because of an error committed by the opposing team

2) Getting to second base by accidentally brushing against a women's breasts.
1) The batter got a base hit, but the ball was overthrown, so he reached second base on an error.

2) Guy 1: How far did you go?
Guy 2: What's it called if we were making out and I accidentally brushed against her titties?
Guy 1: Haha! You totally reached second base on an error.
by Freddy18 January 12, 2011
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