@Felthry The official Unicode word on the matter is this:
U+1F18B NEGATIVE SQUARED IC : interchange, ramp
If you're a Windows user, I recommend BabelMap for identifying such stuff! It's got a bit of the "programmer interface" going on, but it's the right price (free!) and all you really need for cases like this is to copy and paste the character into the edit field and smack F2; the program will find the character and from there you find out all kinds of neat stuff.