As short as it is, it is a loaded, ragged word. It's raw. It looks, when written down, like it should be a comforting word, with the rounded "g" at the front and "f" at the end almost like gentle padding, but: no.
I've felt grief. I've felt it in the Eighties, the Nineties, the Aughts, and this decade. I don't think I did in the Seventies, when I was zero years old to 6 years old, because at those ages you usually, simply can't understand things enough to really feel grief. You can feel sad, but maybe not that level of sad.
(I may be talking out my ass about that age. Child psychologists know far more about how very young children react to the world and sad events that happen in it. I do know I'm lucky to have had a relatively calm, relatively safe childhood; plenty of people, sadly and unfortunately, didn't.)
Grief often stays with you. Maybe it should stay with you, though not at the crushing levels that grief has at the start. My mom once told me that one major event in my youth changed me a lot: the loss of the space shuttle Challenger. I saw that, live, on a day at home (Fairfax County, Virginia schools were closed for teacher workdays). I was 12, an owner of the book The Space Shuttle Operator's Manual and who'd happily been to Cape Canaveral on my family's Florida trip in spring 1984 and who loved to visit the Smithsonian's National Air & Space Museum. As Mom saw, I wasn't really the same kid after that. I'd seen loss, and I had to start living with it. Ignoring it doesn't help; denying it doesn't help. Dealing with it can.
I've had more a little experience with grief. I'm lucky to have experienced a lot of joy as well, a lot of good, but: loss is on my mind.