It's a bit clunky, but I find French often has much neater terms for sailing than English. Essentially, "taper au près" is the phenomenon of slapping in a bumpy way into the waves when sailing close to the wind. Other ways of saying it are "smacking in to the waves", "slamming into the waves", "thumping into the waves", "pounding into the waves" etc. Some boats do this more than others and it depends largely on their hull design (though sail and rigging design also play a part). I've linked a couple of yachtie forums where this phenomenon is being discussed in all these ways below.

This article also calls it "hobby horsing, but in years around yachties in Australia, I have never heard that term: http://www.bytecii.com/tips-and-tricks-tracking-upwind-in-wa...