The word still has several related meanings:

1. Not moving or making noise. A cat might sit perfectly still while watching a bird, frozen in concentration. A lake looks still on a calm day, its surface smooth as glass. When a teacher asks the class to be still, she wants everyone to stop fidgeting and sit quietly.
2. Continuing to happen, even now. If you're still working on your homework after dinner, you haven't finished yet. When someone says “I still remember my first day of school,” they mean that memory hasn't faded. The word often carries a sense of surprise: “You're still playing that video game?” suggests someone has been playing longer than expected.
3. Even more than before, or to a greater degree. When you revise an essay and make it still better, you've improved something that was already good. A kind person might be still kinder to someone having a difficult day.

These meanings connect through the idea of something continuing or remaining: a still pond isn't changing position, and if you're still hungry after lunch, your hunger hasn't changed. The word helps us talk about things that persist or endure when we might expect them to have moved, stopped, or transformed.