Stickiness is the quality of clinging or holding fast to something. Honey has stickiness: touch it and you'll feel it pulling at your fingers, stretching into long strands when you try to pull away. Tape works because of its stickiness. Tree sap, glue, and chewing gum all share this quality of grabbing onto whatever they touch.

Beyond physical adhesion, stickiness also describes things that hold attention or memory. In business, a website has stickiness when visitors keep coming back or stay browsing for a long time. A sticky idea is one that lodges in your mind and won't let go. Think of a catchy song you can't stop humming. That's mental stickiness. Teachers know that stories make lessons stickier than dry facts alone because narratives grab your attention and help information stick in your memory.

Scientists measure the stickiness of materials to design better adhesives or non-stick cookware. The right amount of stickiness in cookie dough holds ingredients together without making the dough impossible to work with. When meteorologists talk about sticky weather, they mean humid air that makes you feel like you're moving through something thick and clingy. Whether describing actual glue or an unforgettable experience, stickiness captures that quality of holding on and not letting go easily.