As an unmarried woman nearing 30, I can't help but roll my eyes a little every time a new "ring shot" graces my Instagram feed. Today, though, I nearly fell out my chair when I learned that mengagement rings—yes, that's engagement rings for dudes—are officially trending. It's true. Way to steal our thunder, guys.

Might Marilyn Monroe be rolling in her grave right now to learn that celebs like Ed Sheeran and Michael Bublé are making a mockery of a girl's best friend with rocks of their own? Perhaps. But, it turns out, we did this to ourselves.

Per Yolanda Spence, manager of the Clear Lake outpost of Robbins Brothers: The Engagement Ring Store, women are the primary purchasers of mengagement rings, and the market's only growing. Both sales and searches for men's engagement rings are up over 66 percent over last year, and the trend shows no sign of slowing.

We surmise the thinking behind mengagement rings is two-pronged: it's a token of a lady's affection for her man, of course, but also a way to show the world he's off the market, too, the same way a shiny rock on a certain finger will (usually) ward off over-eager dudes at bars. But, unlike so many other symbolic gestures, this one isn't generational. It's pretty new.

Men of all ages are taking part, and retailers are responding in kind. Robbins Brothers is stocking more styles and material options than ever before, Spence says, and some men are even getting wedding bands to replace their engagement rings.

So, where to begin? Spence suggests following the same diamond-shopping advice you've probably heard by now and mind the four Cs—cut, clarity, color, and carat. Of course, each aspect will impact how much you're spending, but retailers offer flexible financing options to help you swing your man a princess cut. Our advice: Just don't let his jewelry outshine yours, and you'll be as golden as the ring you place on his finger.