What is dependency in ooad?

Answer 1

It is the relationship between dependent andindependent classes. Any change in the independent class will affect the states of the dependent class

Answer 2

In object-oriented analysis and design (OOAD), dependency represents a relationship between classes where one class relies on another in some way. This reliance can be in the form of one class using services or attributes of another class, or passing instances of one class as arguments to methods in the other class. Dependencies are established through instantiation, method calls, or passing parameters, and they are denoted with a dotted arrow in UML class diagrams.