What is Elo Trading?

On the border of reaching Diamond (Plat 1). Played a game, Picked {{champion:41}} For the first time in ages (Very Bad Idea I know) But I was shit in lane {{champion:39}} OTP is the reasoning. And my midlaner was flaming saying I was "Elo Trading" I mean, I guess it means to trade elo. But what actually is it? We won the game anyway. Cause my ults were just catching guys off guard and enabling engages.
Report as:
Offensive Spam Harassment Incorrect Board