# fuck knows

idiom · Vulgar

Source: https://englishreference.com/idiom/fuck-knows
Updated: 2026-08-10

## Meaning

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

## Examples

- Where he went, fuck knows.
- I asked the manager when the project would finish, but he said fuck knows.
- Why the system failed so catastrophically remains a mystery, and frankly, fuck knows how we will ever fix it.

## Origin

Probably a shortening of "who the fuck knows" (disputed)

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.