Plural of acanthus; multiple acanthus plants or architectural elements.
From Greek 'akantha' + English plural suffix '-es'. The alternate plural 'acanthi' also exists, showing the competition between English and Latin pluralization.
Interestingly, the acanthus plant appears so often in Greek temple carvings that it became more famous as a decorative motif than as an actual plant—architects loved it more than botanists.
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