If you mare has been outside and exposed to the weather, I would suspect rain rot, a fungal skin infection. However, this could also be a bacterial skin infection, external parasite infestation, trauma from bug bites or animal attack, or self-destruction from boredom.
The flank is the lower area of the torso located between the ribs and the hips. It is a fleshy area on the side of the body.
Some of the organs in the flank region include the kidney, part of the liver, and the colon. Additionally, the lower part of the lung and the muscles of the abdominal wall are also found in the flank area.
the hind quarters or hip area
the ellipse is an egg shaped park. 2 buildings that flank it are the white house and the washington monument
The flank of a cat is a part on its body. It is the fleshy area of the side between the ribs and hip in cats it has greater depth than in other breeds, causing considerable depth to the body when viewed from the side.
The flank is the fleshy part where the hind leg meets the abdomen.
Lower back area check out link below
leg-hip area, that's on cuts of meat however in medical terms it can be that or the lower back
Cold sores can be located on the lips, facial area, and genital area.
Canker sores appear as a whitish, round area with a red border. The sores are painful and sensitive to touch.
Flank means Side but im not sure if that applies to people.
Herpes