fiduciary

American  

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

noun

plural

fiduciaries

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

   All investment advisors registered with the Securities and Exchange Commission (SEC) must act as fiduciaries.

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adjective

1. Law. of or relating to the relationship of trust and good faith between a fiduciary and the person for whom the fiduciary acts.

   The executor of a will has a fiduciary duty to act in the best interest of the beneficiary.

   The banks do not assume any financial responsibility—they act in a fiduciary capacity only.

   The American Medical Association said that physicians have a fiduciary responsibility to patients.

2. depending on public confidence for value or currency, as fiat money.

fiduciary British  

/ fɪˈduːʃɪərɪ /

noun

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

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adjective

1. 1. having the nature of a trust

   2. of or relating to a trust or trustee

Other Word Forms

• fiduciarily adverb
• nonfiduciary adjective

Etymology

Origin of fiduciary

First recorded in 1585–95; from Latin fīdūciārius “holding on trust; a trustee,” equivalent to fīdūci(a) “trust” + -ārius -ary

Example Sentences

It has created safe harbors—guidance for the prudent process that is required for the exercise of fiduciary duty.

From The Wall Street Journal • Apr. 2, 2026

“Their response has been that their fiduciary responsibility outweighs any other consideration,” Pritchett said.

From Los Angeles Times • Apr. 2, 2026

Even after the 2024 pact, Overdeck and Siegel quarreled over whether either of them breached their contracts or fiduciary duties, a fight that went into arbitration last year.

From The Wall Street Journal • Apr. 1, 2026

Some of them may be CFPs or another designation that also means they are a fiduciary, but not all of them.

From MarketWatch • Mar. 30, 2026

He prefers money as a concept and often uses terms such as annuity and fiduciary, words definitely not listed in the dictionary of mindless entertainment.

From "Me Talk Pretty One Day" by David Sedaris