What do YOU call it? Social media is divided over the gunk that collects in your eyes overnight - so, did you know its true name?

More from Science & Technology

• Terrifying maps break down exactly who is at risk of new 'super flu' exploding across America... as doctors reveal symptoms you should really worry about

• Covid boosters increase risk of virus that harms brain health, new study finds

• Interstellar object's 'heartbeat' changes as it makes closest approach to Earth in just hours

• Biohacker Bryan Johnson says he will be immortal in 15 years... as he finally 'cracks' the secret to living forever

• What will aliens sound like? As the Disclosure Day trailer sees Emily Blunt seized by an extraterrestrial force, scientists reveal the noises life beyond Earth could really make

• Horrifying leaked footage inside slaughterhouse sparks disgust

• How you can watch premium TV geo-blocked from airing in the UK through a designer BLANKET

• The major UK city that will get driverless trains in 2026

• My brutally honest toddler tested seven of Christmas 2025's hottest toys and she knows exactly what parents should buy

• Mystery as flock of UFOs seen hovering above power station for more than a year

• Britain's worst-case climate scenario laid bare: Terrifying study reveals how temperatures across the UK could plummet 6°C by 2100 - as scientists warn we 'need to prepare'

• The power of swearing: Shouting expletives aloud makes you physically STRONGER by boosting your focus and disinhibition, study finds

• Lost Egyptian temple is unearthed 4,500 years after it was built in honour of the sun god Ra

• Six festive food swaps that will help cut calories over Christmas - and it DOESN'T mean going without your favourites

• Is AI already conscious? Evidence is 'far too limited' to definitively say artificial intelligence hasn't made the leap, expert claims

• The common home appliances that emit TRILLIONS of harmful particles - with the toaster at the top of the list

• Man reveals the bizarre reason you should bring a coconut on your next flight

• Get more Daily Mail content for free: How to add the Daily Mail to Google's preferred sources to find the latest breaking news and best exclusive stories

• Pompeii's victims' last bid for survival: Harrowing study reveals how people desperately threw on heavy woollen cloaks to shield themselves from the falling ash

• 'Ryanair of trains' launches new London to Scotland tickets for less than £35