What condition is characterized by the prolapse and enlargement of the tear gland on a dog's third eyelid?

The condition characterized by the prolapse and enlargement of the tear gland on a dog's third eyelid is indeed Cherry Eye. This occurs when the gland of the third eyelid, which is responsible for producing a significant portion of a dog's tears, becomes displaced or swollen, resulting in a noticeable lump or swelling in the inner corner of the eye.

Cherry Eye is particularly common in certain dog breeds, such as Bulldogs, Beagles, and Cocker Spaniels. It typically requires veterinary intervention, often involving surgical correction to reposition the gland and prevent further issues, such as dry eye or irritation.

In contrast, the other conditions mentioned do not involve the third eyelid gland's prolapse. Pink Eye refers to conjunctivitis, an inflammation of the conjunctiva; Dry Eye is a condition resulting from insufficient tear production, and Glaucoma is a serious eye condition that results from increased intraocular pressure. Each of these conditions presents differently and has its own unique causes and treatments, distinguishing them from Cherry Eye.