Definition of "fiducial" in English

adjective

1. Accepted as a fixed basis of reference.

   • Rulers and coins make good fiducial markers in photographs.

2. Based on having trust.

noun

1. In photography, a familiar reference object used to show size or scale, such as a ruler or a coin; a fiducial marker.

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