To adhere means to stick firmly to something. When you put a sticker on your notebook, it adheres to the cover. Tape adheres to paper. A gecko's feet adhere to walls, letting it climb straight up.

The word also means following rules, beliefs, or plans closely. When students adhere to classroom rules, they follow them carefully and consistently. A scientist might adhere to strict procedures during an experiment to ensure accurate results. If your soccer team adheres to its game plan, everyone sticks with the strategy you practiced.

Adherence is the noun form. Strong adherence to safety rules keeps everyone protected. A chef's adherence to a recipe ensures the dish turns out right.

Notice that adhering to something suggests commitment and persistence. You don't just follow the rule once and forget it. You keep following it. Someone who adheres to their principles doesn't abandon them when things get difficult. The word carries a sense of loyalty and steadfastness, whether you're talking about glue adhering to paper or a person adhering to their values.