trust, faith

Quick Summary

The Latin root word fid means “trust.” This Latin root is the word origin of a good number of English vocabulary words, including confident, fidelity, and perfidy. The Latin root word fid is easily recalled through the popular dog name “Fido,” whom his master can “trust” to be ever loyal.

No Fiddling Around with Fid!

The Latin root word fid means “trust.” When this podcast is over, you will be more confident or thoroughly “trusting” in your ability to recognize English vocabulary formed from the root word fid!

When someone calls her dog “Fido,” she believes that she can “trust” in the loyalty of her dog. This kind of fidelity, or “trustworthiness,” is often more pronounced from dog to human than from human to human! A dog can be the perfect confidant, or someone who can be “trusted” to keep the deepest secret, not barking it about to everyone within ear shot. The secret that you tell to this confidant will assuredly remain confidential, or held in “trust,” at least until your dog learns human speech, at which point he may become “perfidious” or going through your “trust” by telling your secret to another.

Let’s pretend that you have an actual exciting but troublesome secret. You could be diffident or not “trusting” in yourself as to whether or not you should confide in someone, or “trust” that person to keep whatever you have told him in confidence, or in “trust.” Just to be safe, you could have that confidant sign an affidavit, or official written document signed under oath before a public official which ensures that you can “trust” that person to do what he says he was going to do. Or you could simply resign yourself to the fact that humans love to tell secrets, and that there would be a very good chance that the person to whom you told the secret could turn into an infidel, or someone whom you cannot “trust” because he does not uphold principles, in this case the promise to keep your secret.

You can now “trust” that you have a good handle on the root word fid. In fact, you can show great confidence and not merely fiddle around or fidget the next time you meet a word with fid in it!

  1. confident: thoroughly “trusting” yourself in your ability to do something
  2. Fido: dog’s name which means “trusty”
  3. fidelity: “trustworthiness”
  4. confidant: a person whom you can thoroughly “trust” to keep a secret
  5. confidential: of that which is told in “trust”
  6. perfidious: of going through someone’s “trust,” hence breaking it
  7. diffident: not “trusting” oneself
  8. confide: to give sensitive information to someone else to hold in “trust”
  9. confidence: state or condition of being given in “trust”
  10. affidavit: an official written document made under oath to ensure that a statement is “trustworthy”
  11. infidel: a person who cannot be “trusted” to uphold principles of right and wrong
  12. confidence the condition of thoroughly “trusting” in one’s abilities to do something


  • perfidious

    Someone who is perfidious is not loyal and cannot be trusted.

  • diffident

    Someone who is diffident is shy, does not want to draw notice to themselves, and is lacking in self-confidence.

  • confidant

    A confidant is a close and trusted friend to whom you can tell secret matters of importance and remain assured that they will be kept safe.

  • fidelity

    Fidelity towards something, such as a marriage or promise, is faithfulness or loyalty towards it.

  • fiduciary

    A fiduciary relationship arises when one individual has the trust and confidence of another, such as a financial client; subsequently, that trustworthy person is entrusted with the management or protection of the client's money.

  • confident

    If you are confident about something, you are not worried or concerned about it at all because you believe that what you expect to happen will.

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