dependence
Needing someone or something else to live, work, or cope.
Dependence means relying on someone or something else for what you need. When a baby has complete dependence on its parents, it can't survive without their care and feeding. When a town has dependence on a single factory for jobs, the whole community needs that business to stay open.
Dependence often suggests a relationship where one side needs the other to function or survive. A plant's dependence on sunlight means it will wither without light. Your dependence on your alarm clock means you might oversleep without it. Some dependence is natural and healthy: we all depend on food, water, and shelter. Young children naturally have dependence on adults to keep them safe.
But dependence can become a problem when it's excessive or unhealthy. If you develop such dependence on a calculator that you can't do basic math in your head anymore, you've limited your own abilities. When someone has a dependence on a harmful substance, their body or mind has come to need it in a way that harms them.
The opposite of dependence is independence, the ability to take care of yourself and make your own choices. Growing up means gradually shifting from complete dependence on parents toward greater independence, learning to solve problems and handle responsibilities on your own.