貨幣

1. Origins, structure, and basic meaning

• Structure: 貨幣 (かへい) is a noun covering money as a medium-of-exchange system and its physical historical forms.
• Basic usage: 古代の貨幣を観察する concerns individual museum artifacts, while 貨幣の広まり refers to the historical spread of monetary use alongside trade.

2. Common pitfalls and similar expressions

• Artifact level and system level
  • 貨幣 does not have the same countable-object reading in both examples. 古代の貨幣 is observable material, whereas 貨幣の広まり is the abstract spread of a monetary system.