I believe this expression is a bastardisation of the Swahili expression "chupa-chupa", which is a local colloquial expression that means "hurry up". It derives from the Swahili verb "chupa", which means to move quickly (especially through water). It was adopted and adapted as a command by the British during their time as the colonial power in Kenya.

"Chop chop" was an expression meaning "hurry up", directed by the Chinese detective, Charlie Chan, at his assistant in the short black-and-white films of the Charlie Chan mystery series.

The basic rule is that a road should be no steeper than the hill it's climbing.

Why is the word "number" abbreviated to "no" instead of "nu"?

Many abbreviations use the first and the last letters, but sometimes from the English word and sometimes from the Latin derivation. The abbreviation "no" is from the Latin word "numero", which in English means "number". Another example is "ca" from the Latin word "circa", which means "around". English examples include st (street), ct (circuit) and mr (mister). Another interesting Latin abbreviation, used in medicine and written on prescriptions, is "pc" which means "post-culinare", or "after a meal".

John Frith, Paddington