Dependent mean reliant upon something else. A child is dependent upon his parents. If you get sad when it rains, then your mood is dependent on the weather.
Dependent comes from pendant, the French word for "hanging" and literally means "hanging" or "leaning." If you break your leg, you will be dependent, or leaning, on crutches to get around. We also use dependent to show subordination. If you only get new shoes when your Mom has won the lotto, then your foot comfort is dependent on her luck. You can also be a dependent if you’re not financially independent, and someone else pays most of your bills.