English Reference
Idiom idiom

fuck knows

Vulgar

I don't know; nobody knows; it is unclear.

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


SIMPLE

Where he went, fuck knows.

CONTEXTUAL

I asked the manager when the project would finish, but he said fuck knows.

COMPLEX

Why the system failed so catastrophically remains a mystery, and frankly, fuck knows how we will ever fix it.


disputed origin

Probably a shortening of "who the fuck knows"


Related idioms8entries
  1. 01

    as far as one knows

    To the best of one's knowledge, as far as someone knows or possible information to be gathered about the topic, subject, aspect, or situation.

  2. 02

    as you know

    as it is already known.

  3. 03

    fuck if I know

    I have no idea whatsoever

  4. 04

    fuck it

    An expression of great indifference or nonchalance.

  5. 05

    fuck off

    To go to hell; to disappear or go away; to screw oneself.

  6. 06

    fuck someone upside down

    To give someone a bad scolding.

  7. 07

    fuck someone's brains out

    To sexually penetrate (or be penetrated) in a vigorous but pleasurable manner.

  8. 08

    fuck this

    A dismissive expression of great indifference or nonchalance.

Last updated August 10, 2026