@, 4 bytes
Although the language name is 1 byte, outputting the name is astonishingly difficult.
-{}0
This subtracts the string a by 0, which is undefined behavior and thus throws an error:
Traceback (most recent call last):
File "@", line 477, in <module>
res = root.eval()
File "@", line 413, in eval
return self.ins.func(*self.argv, *self.insargs)
File "@", line 115, in insHYPHEN
raise TypeError('-')
TypeError: -
