Depending on the size and location an enclosed field can be called a pasture, paddock, field, or pen.
A small field for horses should provide enough space for them to move around comfortably, graze, and engage in natural behaviors. It should also have access to clean water, shelter from the elements, and be securely fenced to ensure their safety. Regular monitoring and maintenance of the field is important to ensure the horses' well-being.
the field
pasture
It is commonly called a pasture, paddock, or field.
Agricultural horses can be called a team, Race horses can also be called a field Regular horses are more commonly called a herd
A group of wild horses can be called a field, a herd, a set and also a remuda.
The small circle of fur underneath the forelock is called the whorl.
A midget horse is typically referred to as a miniature horse. These horses are known for their small size, typically standing between 34-38 inches tall at the withers. Miniature horses are bred for their small stature and are often kept as pets or used in therapeutic settings.
As in feral horses, yes. There is a rare and small band of feral horses in Africa called the Namib Desert Horses, which are found in the Namib Desert of Namibia, Africa. Please see the related link below for more info.
the field
in a field
Horses are just called "horses" unless they are in a group together. When horses get in a group together, they are then called a "herd".