More pale or light in color; having less color or less intense color than something else, or looking sick or frightened.
From Old English and Latin 'pallidus' (pale). 'Pale' has existed for over a thousand years to describe light coloring, and 'paler' is simply the comparative form. The emotional meaning—pale from fear or illness—developed in the medieval period.
Your face gets pale when blood vessels in your skin constrict—this is literally your body's 'fight or flight' response diverting blood from your skin to your muscles and vital organs. That's why people look ghostly white when terrified or in shock; it's your ancient survival instinct kicking in!
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