The act of damaging something or the process by which something becomes damaged.
From 'damage' plus the suffix '-ment', which creates nouns referring to an action, result, or state; this is an archaic or rare formation in modern English.
Damagement is an old word that almost nobody uses anymore, but it reveals how English constantly creates new words by adding suffixes to existing ones—most of these inventions fail to stick around, but occasionally we stumble across these linguistic fossils in old texts.
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