Things that are substituted for something else; people brought in to take someone's job or position.
From 'replace' (from Old French 'replacer': 're-' + 'placer' meaning to place). The suffix '-ment' creates nouns from verbs, indicating the action or result of replacing.
The suffix '-ment' is incredibly productive in English—you can add it to almost any verb to create a noun meaning the action or result: replace→replacement, achieve→achievement, amaze→amazement!
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