To reduce someone to a lower rank, position, or status, usually as a punishment or due to poor performance.
From de- (down, reverse) + mote (from Latin motus, moving, or from 'motor' positions). The word was created in English in the early 1900s as the opposite of 'promote.'
Demote was invented relatively recently (around 1920s) when businesses needed a quick word for the opposite of promoting someone—it's a perfect example of how English creates new words by combining 'de-' with existing verbs.
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