It's a point where a single failure causes system failure, but that's a lot more words. These things tend to get whittled down to "terms of art", the meaning of

It's a point where a single failure causes system failure, but that's a lot more words. These things tend to get whittled down to "terms of art", the meaning of which is understood by those trained in the art. It's perhaps best to just call it an SPOF and then people will hopefully google it to find out what that means.