European walker
n.— «Several of the yearlings were being exercised in a round pen that features a mechanical walker with a series of moving gates to keep the yearlings separated and moving. “This is what’s called a ‘European’ walker.’”…On the old walkers they were tethered to the walker at their bridle, and that was dangerous. Here, they aren’t tethered, and they have about 20 feet between gates. It’s worked really well for us.”» —“Horse sense” by George Rowand Fauquier Times-Democrat/Citizen (Warrenton, Viriginia) July 20, 2006. (source: Double-Tongued Dictionary)