The majestic Borzoi (Russian Wolfhound)!
Borzoi, or Russian Wolfhounds, look a lot like Greyhounds with long hair. Both are graceful, large sight hounds.
We have some excellent resources for you to explore regarding “Long-Haired Greyhounds” and similar dogs:
You can read about what a sight hound is here.
You can review similar tall, skinny dogs here.
You can discover the basics of Borzoi here.
You can investigate Borzoi Greyhound Mix here.
See also Borzoi vs Horzaya Borzaya
Comparing Borzoi and Greyhounds
The next time someone asks What is a long-haired Greyhound dog called, you will know the answer: Borzoi.