An emblem or symbol; something that represents or symbolizes something else.
From emblem plus the suffix -ment, which comes from Latin -mentum and forms nouns. Though this word exists, it's largely superseded by emblem itself.
English has hundreds of near-synonyms like emblem/emblement that coexist because different suffixes (-ment, -tion, -ure) were applied at different times—the word landscape is literally 'painting of land-scape'!
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