Me at 20 with my college boyfriend in 1972

I was 28 the first time someone suggested I was no longer young.

He was an undergraduate at the university where I was a graduate student in journalism. We were waiting in lines to register for classes, as was done during those pre-digital days.

“Excuse me,” he said, “did you used to be a model?”

This was like asking a guy whether he used to be an athlete – a kind of back-handed compliment that hit the ego’s funny bone enough to twinge, but not so much as to hurt.

Until then, the question had always been “Are you a model,” something that started when I was 16 because I’d been tall and skinny during the Twiggy era and beyond. I never was a model, and although I’m still tall, my skinny days are long gone.

Next time the question of age came up, I wanted to score half off the price of a $12 lamp at Goodwill by taking advantage of its senior-citizen discount. The clerk didn’t think I looked old enough. She carded me to make sure I met the minimum age of 55.

My maternal grandmother, when that age, would not have been questioned. Her gray hair, shapeless house dresses and sensible shoes proclaimed her senior citizenship. My paternal grandmother, even with her dyed hair, manicured nails and stylish wardrobe, thought herself old when she hit 50.

I can’t imagine either of them would have been willing, at the age of 57, to take a job in Beijing for a year, as I did. They would have been physically able, but mentally unequipped.

“The very idea,” I can hear one of them say, “at my age!”

At the age of 61, I expect to live another 25 years or so. My parents, at 86 and 84, are unquestionably old, but they’re still active, pretty healthy and keenly attuned to current events.

When I reach that age, nobody will have to tell me I’m old. But I’m hoping that we Baby Boomers revolutionize old age as our demographic morphs into a Geezer Glut.

A few of my childless, single friends and I fantasize about eventually living together in a bad-old-broads commune. We’d pool our assets, buy a nice place where we could each have our own bedroom and bathroom, and divvy up chores according to ability and interest. At the end of each day, I’d be in a rocking chair on the porch or in front of the fireplace with a shawl around my shoulders, gumming a pot brownie while “Gimme Shelter” blasts through the earbuds of the latest audio gadget.

That’s my goal – to be old enough to know better, and still able to enjoy; to hear some whippersnapper in her 50s, shocked and appalled, scold me about being too old to behave like that.

Rock on, biddies, rock on.