In the field of Economics, Cash simply refers to money. This is the physical form of currency namely, banknotes and coins. Within the context of Bookkeeping and Finance, cash pertains to current assets that include currency or equivalents of such that can easily be accessed. In the case of money market accounts, cash can only be accessed “near-immediately”.
In the instance of structural or incidental negative cash flow, cash may be seen as payment reserve. Cash is also used to avoid a downturn.
In British English, the word cash meant “money box”. As the word evolved, it went on to mean “money” as well. In the 18th century, the secondary meaning became widely accepted, making it the main meaning of the term.