The current description of the "Sportsmanship" badge is:
Up voted 100 competing answers
That misled me at first. I wonder if a few more words might help others avoid the same misunderstanding I made, thinking that "competing answers" referred to any two answers to the same question (i.e. answers that competed with each other, regardless of whether or not I'd answered that question myself), rather than the actual definition: upvoting 100 answers that competed with an answer that I had given to a question, and where my answer has a positive score.
So, the revised description could be something like this:
Up voted 100 answers on questions where an answer of yours has a positive score