No, a cult is like a mental disorder... by definition if it's not causing harm in the person's life it's not a disorder. Many cults disguise themselves as religious groups.
Here's some more differentiators, but you can search "warning signs for a cult"... there's no standard list that I'm aware of.
- Separating people from their outsider friends&family
- Over time absorbing all of member's financial assets
- Punishment for leaving
- Members discouraged from questioning orthodoxy
- Non-volunteer or otherwise coerced unpaid labor
- A culture of hiding information from outsiders
- The leader has exclusive claim to ultimate truth
- Regardless of harm, the leader's behavior is justified