Question

what is pink eye definition?

Answer 1

Pinkeye is also known as conjunctivitis. It happens due to the redness or irritation of the conjunctivae, which are the membranes on the inner eyelids and also covering the whites of the eyes. These membranes respond to various bacteria, viruses, allergy-provoking agents, irritants and other toxic materials. 
Viral and bacterial conjunctivitis are regular during childhood. The main cause of pink eye infection is virus.

Answer 2

Pink eye (conjunctivitis) is an inflammation or infection of the transparent membrane (conjunctiva) that lines your eyelid and covers the white part of your eyeball. When small blood vessels in the conjunctiva become inflamed, they're more visible. This is what causes the whites of your eyes to appear reddish or pink.

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