To make dim or obscure; to reduce brightness or clarity.
From the intensive prefix 'be-' combined with 'dim' (from Old English 'dim'), popular in Middle English for creating verbs expressing thorough or complete action of making something dimmer.
Shakespeare and his contemporaries loved using 'bedim' in poetry—'bedim the stars' sounds so much more dramatic than 'dim the stars,' with the 'be-' prefix giving the verb emotional intensity.
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