The act of devoting or dedicating oneself; archaic term for devotion or dedication.
From 'devote' + -ment (suffix creating nouns from verbs, meaning 'action or result'). This is an older form; 'devotion' is the modern standard.
Medieval and Renaissance writers preferred 'devotement' before 'devotion' took over—it's a linguistic fossil showing how English regularly discards older noun forms in favor of newer ones.
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