I believe its definitely a feeling. The feeling could be towards a place, a group of people, or towards anything else that makes you feel a sense of belonging, that makes you feel that you can be yourself without worrying about it.
I have been living in the same house for the past 8 or 9 years with the same people, in the middle of that I took a break for a while, during that break I found a new home for 6 months.
In this place I felt more at home than I ever felt before in any other place.
It was because of the place, but also because of the people.
It was a place where I could be at peace, with people i didn't have to hide any part of myself from and could be myself without fear.
This is what a home means for me.