Defined

Being dependent on something, being unwilling or unable to stop without adverse side effects

I guess in the strictest sense of the word, we are all addicted to food and sleep. Addiction almost always refers to something negative in use.

Examples

  • If you don’t have your phone, you start to feel Anxiety. That’s the textbook definition of addiction.
  • If you get irritable when you go without smoking, or eating snacks, or whatever.

Source

  • Googles Definition