Index Error or Parallelism?

[Mantaforce]

I am going for my orals soon and I was recently told that the third error of the Sextant is now called Parallelism.

Despite this, any source I look up still says Index Error, so which is the correct answer to give to an examiner?

Thanks

[pignutpilot]

Some people call it index error, some Parallelism. Parallelism is probably better, because you are finding the index error.

Just quickly explain the point to the examiner, he will know exactly what your talking about. Then your won't have to worry about it ever again.