Blue Monday
noun [C]
/ˌbluː.ˈmʌn.deɪ/
the third Monday in January, said to be the most depressing day of the year

Arnall devised a literal mathematical formula to arrive at the Blue Monday theory. It factors in weather, debt and time since Christmas, timing of New Year’s resolutions, low motivational levels, and the urgent feeling that you need to take action. It also reflects that Monday is regarded as the worst day of the week with many dreading the prospect of returning to work.
[www.mnn.com, 15 January 2019]

Fat Cat Friday noun [C]
/ˌfæt.kæt.ˈfraɪ.deɪ/
the third working day (and first Friday) of 2019, by which time the highest-earning UK employees have each already earned more than the average UK employee will earn in the whole of the year

By Friday at 1pm, dubbed “Fat Cat Friday”, chief executives of leading UK companies will have been paid as much as a British worker across 12 months. The figure, which is calculated by looking at the pay of the average chief executive of a FTSE 100 firm, has noted that the average CEO has a pay packet of £3.9m.
[inews.co.uk, 4 January 2019]

Super Saturday noun [C]
UK /ˌsuː.pə.ˈsæt.ə.deɪ/ US /ˌsuː.pɚ.ˈsæt̬.ɚ.deɪ/
the last Saturday before Christmas Day, the day on which shops expect to make the most money in the whole year

Supermarkets have prepared for Super Saturday to be their biggest day of the year, with Sainsbury’s predicting it will ring up £150m in online and in-store sales. Shoppers are expected to buy 1.8m mince pies, four tonnes of sprouts and 400,000 bottles of sparkling wines at the chain.
[www.theguardian.com, 21 December 2018]

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