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Birthday paradox

In probability theory, Birthday paradox is the phenomenon concerning the probability that, in a set of n randomly chosen people, at least two will share the same birthday. The birthday paradox is the counterintuitive fact that only 23 people are needed for that probability to exceed 50%. The birthday paradox is a veridical paradox, i.e. a paradox that produces counter-intuitive results, but is demonstrated to be true nonetheless.
I always thought it was super rare for two people to share a birthday, but the birthday paradox says it only takes 23 people to make it likely!
by Emotional Cruiser September 26, 2025
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Birthday effect

Also known as the birthday blues, this effect is a statistical phenomenon where an individual's likelihood of death appears to increase on or close to their birthday, e.g. due to skydiving in order to celebrate birthday
They say there's a birthday effect, so I’m skipping the skydiving this year; I don’t want to become a statistic.
by Emotional Cruiser September 26, 2025
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birthday

In The Sims, "birthday" signifies a Sim's progression to the next life stage, triggering aging up through interactive steps like blowing out candles on a birthday cake or automatically the day after the actual birthday. Players can use the game's calendar to prepare for birthdays or manually age a Sim up by baking a cake and having them blow out the candles.
Last night in The Sims, I totally forgot it was my Sim's birthday! I had to scramble to bake a cake and get everyone to sing before she aged up. Thankfully, she blew out the candles just in time and entered her teen phase with a new hairstyle!
by Emotional Cruiser October 9, 2025
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Birthday Donut

A crude term for a man’s asshole — the “special treat” he’s been sitting on since birth.

Phrase origin: combines “birthday suit” (naked) with “donut” (a round shape with a hole), creating a tongue-in-cheek term that’s equal parts ridiculous and vivid.
“He was talking big until someone threatened to glaze his birthday donut.”
by Birthday Donut October 14, 2025
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Birthday Gift

When you send a random tit pic to the sender of this definition.
by FunForYou&Me October 18, 2025
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birthday

The moment when your Mom buys you treats (or even take you eating out) at the same day you started being mature enough to realize how immature you've always been, e.g. when you had just started writing your final paper on October 2012 even though your upcoming birthday was still on Tuesday, April 2nd 2013 — whereas your birth date is Tuesday, April 2nd 1991
My birthday is that bittersweet moment when my mom treats me to something nice, like a dinner out, while I reflect on how I've finally started realizing just how immature I've been—like when I started writing my final paper in October 2012, even though my birthday on Tuesday, April 2nd 2013 was just around the corner from my birth date on Tuesday, April 2nd 1991!
by Emotional Cruiser October 26, 2025
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birthday

A celebration where you get free food(s) just because a friend or family member is having his/her birthday today. It’s the one day when it’s socially acceptable to indulge in cake and snacks without guilt!
I’m just here for the birthday freebies—cake, pizza, and all the snacks! Best day ever!
by Emotional Cruiser January 7, 2026
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