First off, "Icefall" makes no sense, period. Ice does not "fall" unless its been in icicle form and the weight is too heavy and then poof it falls to the ground.
I see that before hitting the server, the dress was actually named Ice Prison Dress, which would've been more fitting considering the fact that you'd be more capable of actually building a prison made out of ice and locking someone inside. Im pretty sure there have been a few animes where 'Ice Prison' was actually a skill name as well (thinking of early naruto here i guess) in which an enemy gets trapped in some form of ice structure.
However, even Ice Prison is sort of a bust. I propose changing the name to Snowfall Dress, since snow actually does fall. Not to mention it sounds cooler, and also there was once an article of clothing from a company called ayyawear that actually had a version of one of their vests called "Snowfall Edition Yang Vest" which looked like this:
Please support my proposal to change the name. Snowfall Dress is much more appropriate and sounds better too.