I think all this dumping is because people are tired of waiting for REV2 and are trying to short sell.
Be patient folks, it won't be much longer.
You can't short altcoins, not in the traditional sense. No exchange is allowing people to use margin, with the exception of BTC/LTC on Bitfinex. What you really mean is sell from an existing position in hopes of rebuying lower.
Shhh. Actual meanings of words and phrases don't really matter in the world of cryptocurrency. As long as you know a little jargon relating to financial markets just throw it around whenever it sounds good. It's the evolution of language. Isn't it beautiful? No it isn't.