English Reference
Idiom idiom

fat finger


A supposed cause of typographical errors, especially keyboard errors, caused from erroneous key presses or typing errors on touchscreen devices.

Meaning adapted from Wiktionary, available under CC BY-SA 4.0.


SIMPLE

I made a fat finger error and sent the wrong message.

Be careful not to fat finger the wrong number on your phone.

CONTEXTUAL

I meant to type five dollars, but a fat finger mistake made it fifty instead.

I accidentally fat fingered the delete button while I was trying to save my progress on the report.

The customer service agent apologized for the fat finger typo that listed my address in the wrong city.

COMPLEX

The trader blamed a fat finger for the accidental order that caused a brief fluctuation in the stock market.


The term arises from the mechanical difficulty of using a finger of excessive girth to strike a single key. The physical width of the digit causes it to overlap onto adjacent buttons, resulting in the accidental input of unintended characters. While the visual image suggests a specific anatomical cause, the expression has persisted as a general shorthand for any such clerical error committed during typing.


Related idioms8entries
  1. 01

    all fingers and thumbs

    Of a person, clumsy or awkward.

  2. 02

    big fat

    Complete, utter, total.

  3. 03

    burn one's fingers

    To harm oneself; to suffer consequences of one's actions.

  4. 04

    crack a fat

    To get an erection of the penis.

  5. 05

    fat chance

    Little or no chance, a low or nonexistent likelihood of occurrence or success; a faint chance.

  6. 06

    fat lip

    A swelling on the lip, especially one resulting from a punch or other blow.

  7. 07

    fat of the land

    The greatest part of anything; the finest and most abundant share of resources; the cream of the crop.

  8. 08

    finger in the pie

    A share in the doing of something; involvement.

Last updated August 10, 2026