thirstwave noun [C]
UK /ˈθɜːstweɪv/ US /ˈθɝːstweɪv/
a period of hot, dry weather that causes soil and plants to lose a very large amount of water to evaporation

During a thirstwave, the atmosphere essentially goes into overdrive, demanding more moisture than usual. From 1981 to 2021, thirstwaves across the United States averaged 0.8 millimeters per day above normal, lasted about 4 days, and occurred nearly 3 times per growing season.
[earth.com, 14 April 2025]

firewave noun [C]
UK /ˈfaɪəweɪv/ US /ˈfaɪrweɪv/
a series of fires that burn strongly and out of control on an area of grass in a city, usually triggered by very hot weather

Cities across the UK are facing a growing threat from an emerging phenomenon called “firewaves” as temperatures rise due to climate change, scientists have warned. Guillermo Rein, professor of fire science at Imperial College London, has been working alongside the London Fire Brigade to help predict when conditions are ripe for a “firewave”.
[bbc.co.uk, 14 August 2025]

smog wave noun [C]
UK /ˈsmɒg ˌweɪv/ US /ˈsmɑːg ˌweɪv/
a period of extreme and long-lasting air pollution, where a mixture of smoke, gases, and chemicals in the atmosphere make it difficult to breathe and can be harmful for health

Authorities in eastern Pakistan have closed public parks, zoos, museums, historical buildings and playgrounds for 10 days as a record-breaking “smog wave” choked 18 districts of Punjab province, leaving tens of thousands of people ill. Lahore residents went about their lives in a twilight gloom that lingered over the city for hours, reducing visibility to around 100 metres.
[jerseyeveningpost.com, 8 November 2024]

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best friend dictionary noun [C]
UK /ˌbest frend ˈdɪk.ʃᵊn.ᵊr.i/ US /ˌbest frend ˈdɪk.ʃᵊn.er.i/
a set of inside jokes and made-up words and phrases used by close friends

You know you’re bonded with your best friend when you develop words and phrases of your own, almost like a secret language. On TikTok, this tradition has been dubbed the “best friend dictionary” and it already has millions of views … The best friend dictionary is iconic, but even more impressive is how quickly everyone partaking in this trend seems to know the definitions.
[bustle.com, 14 May 2024]

friendflation noun [U]
/frendˈfleɪ.ʃᵊn/
the rising cost of going out with friends

Can you put a price on friendship? Apparently you can, and it isn’t cheap. The rising cost of socialising, known as “friendflation”, is “becoming a serious pressure point” for many adult friendships, said The Mirror. “Birthdays aren’t just a few drinks at the pub, they’re weekends away, lavish brunches or fancy dinners”, and “even going for a coffee is nearly a fiver”.
[theweek.com, 1 October 2025]

medium friend noun [C]
/ˈmiː.di.əm ˌfrend/
someone who is closer than an acquaintance but not a very close friend

I personally don’t think that it makes sense to go around calling people medium friends to their face. This term is more about internal taxonomy so that you can name and understand the phenomenon without feeling like you’re the only person experiencing this or feeling bad for it.
[reeswrites.com, 1 June 2025]

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ber month noun [C, usually plural]
UK /ˈbɜː ˌmʌnθ/ US /ˈbɝː ˌmʌnθ/
one of September, October, November or December

The ber months are calling. Whether it’s September’s gentle sun, October’s adventures, November’s tropical retreats or December’s festive warmth, there’s a perfect escape waiting for you. Imagine waking up to golden beaches, exploring vibrant cities or discovering wellness retreats that leave you completely recharged.
[notjusttravel.com, 4 September 2025]

October theory noun [S]
UK /ɒkˈtəʊ.bə ˌθɪə.ri/ US /ɑːkˈtoʊ.bɚ ˌθɪr.i/
the belief that October is a like a second New Year, giving people the chance to set new goals and make important life changes

Many users across the platform have increasingly been posting about the “October theory,” and what that means for the rest of the year. According to Chloe Van Berkel, a content creator on TikTok, October is almost like New Year’s Day. The month kicks off the start of the fourth quarter of the year … a reflective period in which people look back on their year to see what they’ve accomplished.
[independent.co.uk, 3 October 2024]

summerween noun [C or U]
UK /ˌsʌm.ə.ˈwiːn/ US /ˌsʌm.ɚ.ˈwiːn/
a celebration of Halloween held in the summer instead of on 31 October

Summerween is a playful blend of summer vibes and Halloween thrills. Imagine sipping your favorite icy drink while surrounded by spooky skeletons and glowing pumpkins. It’s the best of both worlds! This quirky trend is catching on, giving Halloween enthusiasts an extra reason to celebrate and decorate months in advance.
[parade.com, 14 July 2025]

About new words