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obsidional coin

American  
[uhb-sid-ee-uh-nl] / əbˈsɪd i ə nl /

noun

  1. siege piece.


Etymology

Origin of obsidional coin

1800–10; < Latin obsidiōnālis of a siege, equivalent to obsid ( ēre ) to besiege + -iōn- -ion + -ālis -al 1