[ fi-doo-shee-er-ee, -dyoo- ]
/ fɪˈdu ʃiˌɛr i, -ˈdyu- /

noun, plural fi·du·ci·ar·ies.

Law. a person to whom property or power is entrusted for the benefit of another.


Law. of or relating to the relation between a fiduciary and his or her principal: a fiduciary capacity; a fiduciary duty.
of, based on, or in the nature of trust and confidence, as in public affairs: a fiduciary obligation of government employees.
depending on public confidence for value or currency, as fiat money.


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Origin of fiduciary

1585–95; < Latin fīdūciārius of something held in trust, equivalent to fīdūci(a) trust + -ārius -ary


fi·du·ci·ar·i·ly, adverbnon·fi·du·ci·ar·y, adjective, noun, plural non·fi·du·ci·ar·ies. Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

British Dictionary definitions for non-fiduciary

/ (fɪˈduːʃɪərɪ) law /

noun plural -aries

a person bound to act for another's benefit, as a trustee in relation to his beneficiary


  1. having the nature of a trust
  2. of or relating to a trust or trustee

Derived forms of fiduciary

fiduciarily, adverb

Word Origin for fiduciary

C17: from Latin fīdūciārius relating to something held in trust, from fīdūcia trust; see fiducial
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012