To make something smaller or diminish in size; to reduce or belittle.
From 'en-' (causative prefix) + 'small' (from Old English 'smæl'). The verb form emerged in Middle English by adding the productive causative prefix to the adjective, creating a verb meaning 'to cause to become small.'
English once had many verbs formed this way—'enbiggen' meant to enlarge—but most have fallen out of use except in literature and occasionally in playful modern language (like The Simpsons' famous 'embiggen').
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