D defs.my
Entry 2 senses Webster, 1913

Fiducial

· Fi·du·cial · IPA /fəˈd(j)uːʃəl/
01 a. Having faith or trust; confident; undoubting; firm.
  1. 1.
    Having faith or trust; confident; undoubting; firm.
  2. 2.
    Having the nature of a trust; fiduciary; as, fiducial power.
Phrases & compounds
Fiducial edge — the straight edge of the alidade or ruler along which a straight line is to be drawn.
Fiducial line — a line or point of reference, as for setting a graduated circle or scale used for measurments.