Tooth

It stands for teeth and everything that happens to them. The picture is a molar, the broad grinding tooth at the back of the mouth, shown clean and white with its roots exposed, the way a dentist's poster would draw it. Nothing in the design hints at pain or decay; the message around it supplies the mood.

Most messages use it literally. "Dentist at 3 🦷" announces an appointment; "🦷😭" after "my face is swollen" means a toothache or an extraction; "got my braces off 🦷✨" and "wisdom teeth out, living on soup 🦷🥣" are the big life updates it was practically made for. Parents send it with a photo of a gap-toothed grin, and dentists and hygienists use it on their social posts and appointment reminders. It is one of the rare emoji that is almost never flirtatious or sarcastic: when someone sends you a tooth, they mean a tooth.

Why put 🦷 on a child's photo?

It celebrates a lost baby tooth. Children lose their first set of teeth from about age six, and most cultures mark the moment. In the US and other English-speaking countries the Tooth Fairy leaves a coin or small gift for a tooth under the pillow, a custom that took shape in the early 20th century. Spain has Ratoncito Pérez, a little mouse made famous by Luis Coloma's 1894 story for the child king Alfonso XIII; Latin American countries have tooth mice under local names, and France has la petite souris, "the little mouse".

In Japan the lower tooth is thrown onto the roof and the upper one under the floor or into the ground, so the new tooth grows straight toward the old one, and children in Korea, Vietnam and other parts of Asia toss teeth onto the roof too. So a 🦷 next to a six-year-old's photo is a proud milestone, not a trip to the dentist, and the reply it wants is congratulations.