Before one can say Jack Robinson.
This proverb means that something happens so quickly that it is hard to believe or before one has time to react.
Jack Robinson is a name present in two common figures of speech.
When referring to Jack Robinson, it is used to represent quickness. Connoting quickness
Multiple citations explain references to Jack Robinson as meaning quickness of thought or deed. The normal usage is, "(something is done) faster than you can say Jack Robinson", or otherwise, "before you can say Jack Robinson".
- The phrase first appeared in print in 1778 in Frances Burney's novel Evelina ("I'd do it as soon as say Jack Robinson"), but probably was in wide use before that time.
Connoting slowness or roundaboutness
In contrast, the phrase "(A)round Jack Robinson's barn" has the opposite connotation, implying slowness, as it is often used to refer to circumlocution, circumvention, or doing things in roundabout or unnecessarily complicated ways.
Interestingly, Jack Robinson is ideed very easy to pronounce, may not be the shortest phrase though.
I tried it with different speed, tones, or loudness, my tongue never stumbled or slipped.
On the contrary, "(A)round Jack Robinson's barn" is bit tongue twisting, I had to slow down.
