Actually, that's not true.
Possibly as late as the 17th or early 18th century, it was in common use and meant to penetrate or to strike. When it was original used as a word for fornication, it was vulgar and was "slang" or improper. Again, you can never take language to literally for exactly that reason. Your gripe, as you've mentioned it, is false because you weren't aware of the full history of the word. It's current "real" meaning, as you know it, developed from slang use of the word hundreds of years ago.
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