You may have heard mention of a dog having a third eyelid, but is it true? And what does it mean? There are lots of dog facts that are still unknown to the average person, even to proud dog parents. So, there’s always more to learn about our canine companions, such as their unusual eyelid setup. Do Dogs Have a Third Eyelid? Yes, dogs have a third eyelid. They have a top and bottom eyelid just like humans do, but then, they have an extra eyelid that's thin and swipes sideways
