Proper terminology could be, the right lover/partner for me (right now).
Or, the perfect lover/partner for me (right now).

They could also say soul mate provided they then meant the above and not "The one and only perfect lover in existence for me this lifetime."
There is no "one great love this lifetime", and most of us who have been in several relationships should know this. Someone could be a lasting partner, the love we stay happily in relationship with for the rest of our life, but we all know there is no guarantee.
I do feel we should have the intention that it's going to be a lasting relationship as you then enter it with a different, healthy mindset.

But if it doesn't work out... Even after a lover that was once great there are always chances of a new great love, and another, and another.
There isn't this "only one perfect match for me" that many seem to be focused on and looking for.

And that's great news as it means we can always find love. Even if we'd be moving to China, Russia, the other side of the country, or stay where we are.

What you generally see is that the ones looking for this 'one great love this lifetime' are desperate, in fear, not standing solidly on their own two feet, lack self-esteem etc. so they latch on to some external idea that they think will solve all their problems and make them feel better.
Confident and stable people know that is a flawed premise and they wouldn't work nor think that way.