Operation Yellowhammer
noun phrase

- The codename used by the UK Treasury for cross-government civil contingency planning for the possibility of a "no-deal" Brexit.

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In the event of no-deal, the UK's unilateral departure from the EU would disrupt, for an unknown duration, many aspects of the relationship between the UK and European Union, including financial transfers, movement of people, trade, customs and other regulations.

Operation Yellowhammer is intended to mitigate, within the UK, the effects of this disruption, and would be expected to run for approximately 3 months.

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CODE NAME

Code name or cryptonym is a word or name used, sometimes secretly, to refer to another name, word, project or person. Names are often used for military purposes, or in espionage. They may also be used in industrial counter-industrial espionage to protect secret projects and the like from business rivals, or to  give names to projects whose marketing name has not yet been determined.

Throughout the Second World War, the British favoured one-word or compound code names Alphabet, Boomerang, Carthage, Dukedom, Escort, Foxchase, Goodwood,... Overlord (the codename for the Battle of Normandy) was personally chosen by Winston Churchill himself.

Churchill was particular about the quality of code names. He insisted that code words, especially for dangerous operations, not be overly grand nor petty nor common. One emotional goal he mentions is to never have to report to anyone that their son "was killed in an operation called 'Bunnyhug' or 'Ballyhoo'.

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THE BIRD, THE SONG

The yellowhammer (Emberiza citrinella) is a songbird in the bunting family that is native to Eurasia and has been introduced to New Zealand and Australia. The male yellowhammer has a bright yellow head, streaked brown back, chestnut rump and yellow underparts.

This conspicuous yellow bird has inspired poems by Robert Burns and John Clare, and its characteristic song has influenced works by Beethoven and Messiaen.

The over-imaginative interpret the yellowhammer's song as a call for “a little bit of bread and no cheese”. That notion was popularised by Enid Blyton, who mentioned it in at least one of her Famous Five books – Five Go Off in a Caravan – and also embellished it in a children’s poem.

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THE STATE

Alabama is nicknamed the Yellowhammer State. The yellowhammer, also known as the northern flicker or yellow-shafted flicker, became the official state bird of Alabama in 1927.

Soldiers from Alabama were nicknamed “yellowhammers” in the Civil War due to their grey-and-yellow uniforms, which matched the colours of the bird.

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Sources:

- "HyperWar: Glossary of Abbreviations, Acronyms, Codewords, Terms of WWII"
- "Churchill, the Great Game and Total War" Jablonsky, David
- "Enid Blyton's Nature Lover's Book" Blyton, Enid
- "Birds Britannica. London" Mabey, Richard