an 'eye' window

I dont know if it's a real name but we called it an eye window. Today we had sunshine, cloud, a few drops of rain and then it was very warm. This evening we tempted 'the dog' out again and returned to his place of antics for half an hour so. Recently I blipped the old building and today we looked at the windows and doors. The information board tells us this Manor was built on the site of a priory, it's construction typical of the 16th century made up of a large room and embellished with two monumental chimneys. Over the years there have been additions, this door and window looked to have some sort of repair.