know sth back to front

/nˈəʊ ˌɛstˌiːˈeɪtʃ bˈak tə fɹˈʌnt/

/nˈoʊ ˌɛstˌiːˈeɪtʃ bˈæk tə fɹˈʌnt/

[phrase]

to know sth back to front

[PHRASE]

to be really familiar with a particular subject, place, etc.

The origin of the idiom "know something back to front" is straightforward. It uses the spatial metaphors of "front" and "back" to convey a deep level of familiarity or knowledge with a particular subject or object. This expression is used to describe a high level of expertise or comprehensive knowledge about a subject, task, or object. It suggests that the person knows every aspect or detail thoroughly, similar to knowing the front and back of a book. It can be applied in various contexts, such as work, hobbies, or academic subjects.

Examples

1. The book corresponded so exactly with Ulvskog's portrayals that either he knew the book back to front or he had been there himself.

2. BEN AFFLECK, Actor: You have to know your resume back to front.

3. So we rehearsed the whole thing all the way through a bunch of times, so we just knew the thing back to front.

4. I don't care if you know the entire textbook back to front.