Is the name kernel panic being used outside of Linux-based systems?
The original v1 version of Unix had a label in the source code (assembly language) called
panic:. If something went wrong elsewhere, code would jump to there and the system would reboot (that's an assumption given a comment in the code, in contradiction to the Van Vleck quote). The string "kernel panic" does not appear there, but this would appear to be the origin of kernel panic in Unix.
The term has continued to be used throughout the lifetime of Unix and its derivatives.
As recounted by Tom Van Vleck:
I remarked to Dennis that easily half the code I was writing in Multics was error recovery code. He said, “We left all that stuff out. If there's an error, we have this routine called panic, and when it is called, the machine crashes, and you holler down the hall, ‘Hey, reboot it.’”