fiduciary

American  

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

noun

fiduciaries plural

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

Derived Forms

• nonfiduciary
  adjective
• fiduciarily
  adverb

Inflected Forms

Nouns

• fiduciaries
  plural

Etymology

Origin of fiduciary

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

Explanation

A fiduciary is a person who holds assets in trust for someone else. That person has a fiduciary duty to take care of the money. Fiduciary comes from the Latin word fidere, "to trust." That's because a fiduciary is the person you trust to hold and watch over your assets until it's time for them to go to another designated person. For example, when a child's parents die, someone is chosen to look after the money left in the will until the child is old enough to manage it himself. Fiduciary can either be a noun to refer to the caretaker or an adjective to describe the trust.

Example Sentences

Another key point: OpenAI’s personal-finance feature is not a registered adviser or fiduciary.

From MarketWatch • Jul. 1, 2026

This can create interesting opportunities, when an investment is available to you that a fiduciary might find hard to buy for clients.

From MarketWatch • Jun. 26, 2026

“If you have an adviser who’s held to a fiduciary standard, then there is some accountability if they give you bad advice,” Allison says.

From The Wall Street Journal • Jun. 25, 2026

Broker-dealers are excluded from a fiduciary standard, unless they are dually registered as investment advisers or offer ongoing retirement financial advice.

From MarketWatch • Jun. 16, 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