For me open-minded means to not feel attacked or uncomfortable or alienated when someone is different from me in thinking, being, looks .. whatever, and to not judge others or follow any generalisations.
In my eyes it is often like that that people consider themselves as open-minded, but it is almost the opposite. Their mind or soul feel "tight" and not open for me because they have limits in how they see the world, so that they are not able to even imagine there is more than their world.
I took your words with me outside on our terrace and cleaned a hand lantern (very interesting :-)). First I thought a soulmate is maybe someone who feels so much familiar that her or his love is never a question and can never go away (sorry for the simple way to express myself) because both love in the same way each other and themselves, too. But maybe it is also more a coincidence that you met someone who was raised excactly the same way with all the little good and not so good mechanisms, and the same emotional, unspoken things make you feel so extremely comfortable. Ah, is that difficult (<--- international body language :-))
I am not sure, but maybe a soulmate is someone with whom the silent moments feel complete without thinking about it. Or that you feel as if you belong to each other because this person is the only one of whom you are sure your innermost communicates with his in a way that feels like coming home or being reunited. It must feel as if you have found the emotional basis, protection and infinity, I think.
RE: New Word with last letter of the one above
yes