# know one's shit

idiom · Vulgar

Source: https://englishreference.com/idiom/know-ones-shit
Updated: 2026-08-10

## Meaning

Synonym of know one's stuff, to be knowledgeable about a subject or task.

## Examples

- Ask Sarah for help because she really knows her shit.
- You should trust the new mechanic with your car because he clearly knows his shit.
- Despite his casual demeanor, the lead developer knows his shit and can solve any technical problem that arises.

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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.