fiducial

/F AH0 D UW1 SH IY0 AH0 L/
noun
  1. 1

    In manufacturing, a small mark on a circuit board used to align components, a fiducial point.

adjective
  1. 1

    Accepted as a fixed basis of reference.

  2. 2

    Based on having trust.

Source: https://en.wiktionary.org/wiki/fiducial