Liquidity
Also: liquid, illiquidity
How quickly an asset can be turned into cash without materially moving its price.
Cash and listed equities are highly liquid; private equity and real estate are not. A liquidity floor — the share of the portfolio that must remain accessible within a set horizon — is a common policy constraint.
Liquidity tends to be abundant when it is not needed and scarce when it is. The time to fix a liquidity floor is in calm markets, written into the policy, not mid-crisis, when raising cash means selling good assets cheaply.