Liquidity (emphasis on the second "and") is an economic term, meaning the degree of realizability in the market of any asset (commodity, service or security). Realizability here means the opportunity to buy or sell a large quantity of goods at a price close to the market price.
They say that the stock is "highly liquid" if on any trading day you can sell or buy a large amount of such shares at a stock exchange at prices close to the current quotes. Conversely, if you have a large stock of first-class 1.44-inch floppy disks, in the 21st century, nobody needs this product for a long time and is called "illiquid". You can sell a lot of floppy disks only at a symbolic price to some amateur retro computer enthusiast.
The word "liquid" in Latin means "liquid", which, as it were, hints at the "fluidity" of liquid assets from one source to another.
Liquidity is in the list: Economy