Oh, I bet Maple's guessed it again!
The word in my mind has nine letters. It's a noun and an adjective. As a noun, it's very slender.
TanitIs it something that you can ...... lift?... own?... buy?
...lift? --No.
...buy? --I don't think so.
...own?--Yes, you own them, but not in the common sense of "own". More likely, you HAVE many of them.