What is the common name for conjunctivitis?

Conjunctivitis is commonly referred to as "pink eye" due to the characteristic redness and inflammation of the conjunctiva, which is the membrane that covers the white part of the eyeball and the inside of the eyelids. This condition can result from various causes, including viral or bacterial infections, allergens, or irritants, leading to symptoms such as redness, itching, and discharge. The term "pink eye" effectively describes the noticeable changes in the eye's appearance, making it easily recognizable to both healthcare professionals and the public.

The other terms listed do not accurately represent conjunctivitis. "Red eye" is a broader term that may refer to any condition causing redness in the eye, which can include conjunctivitis but is not specific. "Dry eye" refers to a different condition characterized by a lack of moisture on the eye's surface, and "dark circles" involves discoloration under the eyes, often unrelated to conjunctivitis. Thus, "pink eye" is the most specific and widely understood name associated with conjunctivitis.