gradually
Slowly happening over time, in small steps.
Gradually means happening slowly over time, in small steps rather than all at once. When ice cream melts gradually on a hot day, it doesn't turn to liquid instantly. It softens bit by bit until eventually it's a puddle. When you gradually improve at piano, you don't suddenly become a master. You get a little better each week through practice.
The word suggests a gentle, steady pace of change. A sunrise happens gradually: the sky doesn't flip from dark to light like a light switch. Instead, it moves through deep blue, then purple, then pink, then orange, before becoming bright daylight. When a teacher gradually increases homework difficulty, students have time to build their skills instead of feeling overwhelmed by sudden jumps.
You'll often see gradually paired with its opposite, suddenly. A balloon deflates gradually when air leaks out slowly, but pops suddenly when it bursts. Understanding gradually helps you notice that many important changes in life, like growing taller, learning to read better, or becoming more responsible, don't happen overnight. They unfold slowly, sometimes so slowly you barely notice them happening until you look back and realize how far you've come.