As a verb, it means to change something into a different form, use, or belief. As a noun, it is a person who has changed their beliefs, especially their religion.
From Latin *convertere* 'to turn around, transform', from *con-* 'together' and *vertere* 'to turn'. Over time it came to mean turning from one state or belief to another.
Whether you convert units (meters to feet) or religions, you’re 'turning' from one system to another. The stress pattern again signals meaning: CON-vert is the person, con-VERT is the action. In many cultures, being a convert can reshape your social world as much as your inner beliefs.
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