People make up their own definitions sometimes to suit their own situation or sometimes to get views on social media but it’s basically the theory of meeting your other self. One soul incarnated into two bodies.
Some call it divine feminine (DF or positive polarity) and divine masculine (DM or negative polarity.) So a man can be a DF and a woman the DM, or both could be the same gender. You’re always connected at the 5th dimension level, but not necessarily at the 3rd dimension level. I read that it’s rare for both polarities to incarnate at the same time and normally one stays in the 5th dimension as a spirit guide.
A lot of people think the purpose is romance or a mission. But supposedly, a true twin flame’s purpose is to spiritually wake you up? You don’t need anyone to start doing mission work and a soul mate is better for romantic relationships (IMO.) The energy in the connection apparently moves differently than a normal relationship. You can be platonic TFs for a while, but it won’t last like that.
For many (not my experience) they start dating briefly and then one ends it and the other goes into ego death. Ego death isn’t for the faint of heart and as hard as it sounds you only wish it was that easy. The obsessive thinking on the person is horrible and just keeping busy with hobbies isn’t enough. All your mental energy pours out to them which makes them run more. This is when many go looking for help to stop the intrusive thoughts. The best way is to block them physically and on social media, not out of spite, but to pull the energy back to you.
Some experience a Kundalini Awakening with it. The law of attraction can kick into overdrive. Many start seeing signs and numbers. Some flames actually look alike, especially around the eyes. But here’s what confuses me, how do you know if someone’s your twin flame vs just a catalyst?