The opportunity cost of holding money is the value of the next best alternative to holding money. When you hold wealth in the form of money instead of some other interest-bearing asset, such as bonds, you are giving up interest that you could be earning on other forms of financial assets.

inflation is asset value lost due to changes in purchasing power. The opportunity cost of something is the value of the next best alternative, but risk is uncertainty about the value of an asset in the future.

Liquidity is the ability to convert the value of an asset into cash, not the value that is given up by holding wealth in the form of money rather than a different kind of financial asset.

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