Gabor Mate’s definition of addiction

From In the Realm of Hungry Ghosts, pg 136-137:

There is a fundamental addiction process that can express itself in many ways, through many different habits. The use of substances like heroin, cocaine, nicotine and alcohol are only the most obvious examples, the most laden with the risk of physiological and medical consequences. Many behavioural, nonsubstance addictions can also be highly destructive to physical health, psychological balance, and personal and social relationships. Addiction is any repeated behaviour, substance-related or not, in which a person feels compelled to persist, regardless of its negative impact on his life and the lives of others. Addiction involves:

1. compulsive engagement with the behaviour, a preoccupation
   with it;
2. impaired control over the behaviour;
3. persistence or relapse, despite evidence of harm; and
4. dissatisfaction, irritability or intense craving when the object—
   be it a drug, activity or other goal—is not immediately available.

Compulsion, impaired control, persistence, irritability, relapse and
craving—these are the hallmarks of addiction—any addiction. Not all
harmful compulsions are addictions, though: an obsessive-compulsive,
for example, also has impaired control and persists in a ritualized and
psychologically debilitating behaviour such as, say, repeated hand
washing. The difference is that he has no craving for it and, unlike the
addict, he gets no kick out of his compulsion.