What Does Natsukashii Mean?

A word so dear to me, first read about in Finding Adam by Martha Beck, where she explains it as follows: "'Natsukashii' is a Japanese word that described exactly what I was feeling: a wistful sense of longing, an appreciation for beauty laced with sadness at its transience..."

Also defined by a now-obsolete blog called Wanderings and Wonderings, a definition I really like as well:
"Natsukashii is one of those Japanese words that is quite difficult to render into English; poignant might be a close approximation. It signifies the tinge of sadness that comes with the reminder of/remembering familiar things. Maybe a place that was once significant and not longer is, but nevertheless, still holds emotional appeal." 

For me, "natsukashii" is that feeling of achy joy at anything I treasure that is fleeting, or anything dear to me that has already passed into the past. I believe I am an avid memory-keeper, via journaling, taking photos, blogging, etc., so I can attempt to hang onto these treasured moments and feelings, even just a little... though these photographs and words I create are often the source of all natsukashii for me. And that's okay. It's a beautiful feeling, even when it aches.