Chop chop
Tell someone to hurry up than telling them to "chop-chop" -- especially if the phrase is accompanied by clapping or snapping fingers.
Several etymological dictionaries trace the origins of the word to a version of pidgin English used on ships (and later by Chinese servants and traders who regularly interacted with foreigners). The Oxford English Dictionary traces the first usage of "chop chop" in print to an 1834 article in the Canton (Ohio) Register. Two years later, it would also appear in The Penny Magazine, an illustrated English publication geared toward the working class. In an 1838 article, "Chinese English," the magazine defined "chop-chop" as "the sooner the better," but made no mention of the phase being rude or curt.
According to Hobson-Jobson: The Definitive Glossary of British India, the noted Anglo-Indian dictionary published in 1886, the phrase originates from the Cantonese word kap, or 急 (which means "make haste"). In Mandarin, the word is jí, and in Malay it's chepat. This evolved into "chop-chop" and was quickly picked up by the Englishmen who traveled the Asian seas.
The utterance "chop-chop" would also become closely associated with class over time, and was almost always said by someone powerful to someone "below." A good example of this can be found in William C. Hunter's 1882 history of life in Canton, or Guangzhou, China, where he notes that "[w]hen a coolie is sent on an errand requiring haste, he is told to go 'chop-chop.' "
By the 1900s, "chop-chop" had become an established part of military jargon, with the "chop-chop signal" included in the U.S. Army's 1916 Signal book and with the phrase commonly being used to mean "hurry, hurry." Former soldier Eugene G. Schulz described how Army officers would snap at soldiers in his memoir of World War II.