The act or process of expressing; expression or the manner in which something is expressed.
From 'express' plus the suffix '-ure' meaning 'act or process of' (from Latin -ura). This archaic form was more common in Middle English but has largely been replaced by the simpler 'expression.'
Expressure is an old-fashioned word that fell out of favor because English preferred the simpler 'expression'—it's a reminder that languages naturally prune their vocabulary to eliminate near-synonyms over time.
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