trick, deceive, be in error

Quick Summary

The root words fall and fals come from a Latin word that means to ‘trick.’ Some common words derived from this root word are false and fault. Watch out for the ‘tricks’ this root can play, for the word faucet (tap) is also derived from this root word, and you’ll probably be surprised to learn why.

Of Popes and Tricky Pipes

There are some truly interesting English vocabulary words that come from the roots fall and fals which mean to ‘trick.’

For instance, consider the word false. If an answer is false, it has tried to ‘trick’ someone into thinking it is true. When you falsify information, you ‘trick’ others into thinking something is true, when it, in fact, is not.

A fallacy is a ‘deceptive’ belief or notion. In the same vein, a fallacious statement is misleading or trying to ‘trick’ its readers.

If someone is infallible you mean that she cannot be ‘tricked,’ that is, she cannot make errors. The Pope is often considered infallible because he is believed to be unable to make errors when it comes to spiritual matters.

The word fault comes from this root as well. If you are at fault in a matter, you were ‘tricked’ into doing the wrong thing, perhaps due to lack of good judgment. A fault in the earth is ‘tricking’ you because the ground there is not quite as solid as it appears to be. When someone defaults on a loan, she has ‘tricked’ the bank by not paying her loan installments on time.

The most interesting etymology with this root is probably the word faucet (tap). Picture a closed faucet. It is ironically ‘tricking’ you into thinking there is no water available, although the pipe is actually full!

  1. false: a ‘deceptive’ truth
  2. falsify: to ‘make a trick’
  3. fallacious: ‘deceptive’
  4. fallacy: a ‘deceptive’ notion
  5. infallible: ‘not capable of being tricked’
  6. fallible: ‘capable of being tricked’
  7. faucet: a ‘deceptive’ plumbing apparatus


  • fallacy

    A fallacy is an idea or belief that is false.

  • infallible

    If something is infallible, it is never wrong and so is incapable of making mistakes.

  • failure

    an act that fails

  • fallacious

    containing or based on a fallacy

  • fallibility

    the likelihood of making errors

  • fallible

    likely to fail or make errors

  • false

    not in accordance with the fact or reality or actuality

  • falsification

    any evidence that helps to establish the falsity of something

  • fault

    a wrong action attributable to bad judgment, ignorance, or inattention

  • infallibility

    the quality of never making an error

  • unfailing

    not liable to failure

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