before sb can / could say jack robinson

/bɪfˌɔːɹ ˌɛsbˈiː kan ɔː kʊd sˈeɪ dʒˈak ɹˈɒbɪnsən/

/bɪfˌoːɹ ˌɛsbˈiː kæn ɔːɹ kʊd sˈeɪ dʒˈæk ɹˈɑːbɪnsən/

[phrase]

[PHRASE]

so suddenly or quickly that leaves one with no time to react or notice anything

What is the origin of the idiom "before someone can say Jack Robinson" and when to use it?

The exact origin of the idiom "before someone can say Jack Robinson" is uncertain, but it has been in use since at least the 18th century. It is believed to have emerged in England and is often employed in storytelling, anecdotes, or casual conversations to describe instances where something happens rapidly or unexpectedly.

Examples

1. I'll be back quicker than you can say Jack Robinson.

2. You lost the race faster than you can say Jack Robinson.