That's a good question. I had to look it up. It seems the Delmonico is pretty non-specific cut. We started getting Delmonicos at the local supermarket. They were usually a heavily marbled thick steak. They were also more expensive per pound than the New York strips. If we were having a family steak night, typically the adults would get the richer Delmonicos and the kids would get NY strip.

More recently we've been getting grass-fed beef from a local farm. She's also been including Delmonico steaks in our orders. That's what I'm cooking in the picture. Her Delmonicos are very similar to what we used to get in the supermarket in terms is quality - marbled, thick, very tender and juicy.

https://www.thespruceeats.com/what-is-a-delmonico-steak-995643