The state or condition of being without eyes or being unable to see.
From 'eyeless' + '-ness' (Old English -nes forming abstract nouns). Double suffix (eye + -less + -ness) creates an abstract noun from the adjective.
The eyelessness of creatures like the hagfish is actually an adaptation—they hunt by smell and touch in murky water, and eyes would just get infected with parasites, so evolution traded them away for a better survival strategy.
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