Keywords: money, financial, glossary, definition, definitions, terms, currency,

Here is a Numismatic Glossary that's pretty good: http://www.coin-gallery.com/cgglossary.htm

The following is taken, largely, from

Helicopter Money - Irredeemable fiat money and the liquidity trap

by Willem H. Buiter

The terms are from the endowment economy model with a flexible price level

'the Sovereign'	informally, the state. the consolidated General Government and central bank
‘Government’	the consolidated General Government and central bank
'specie'	precious metal used to back money.	Qualified as i) only gold or silver or ii) only the metal in self-backed money (the metal in coins, essentially)
'legal tender'	1) folk (dictionary) definition: a means of payment (currency) than cannot be refused if it is offered (tendered (usually up to a limited amount)) to settle a debt or other financial obligation. 2) legal definition: a legally defined means of payment that should not be refused by a creditor in satisfaction of a debt. Thus, if a debtor pays in legal tender the exact amount owed under the terms of a contract, there is a strong prima-facie defence in law, against suit for non-payment.
'money, ur'	A barter commodity which, by its wide marketability has gradually acquired a second use as a medium of exchange through which one specialized product can be exchanged for another.	Attributes adding to a commodity's marketability are: portability, durability, fungibility, value stability - lowest 'wobble' (Wanniski Gold Polaris), I.E., immune to supply shocks and demand shocks (Fekete), resistance to communicable disease vectors, no seigniorage, divisibility, mass (weight) easily determined (includes non-counterfeitability) recognizability, ... above-the-ground supply is a large multiple of annual output (stocks-to-flows ratio is high[est]) (stocks-to-flows ratio is estimated to be greater than 50 for gold but estimated to be less than 0.25 for copper) The large stocks-to-flows ratio reveals the willingness of people to carry the money (typically a monetary metal), in spite of carrying charges, and defying government propaganda. (Fekete, Fekete 2)
'money, Aristotle's definition'		1.) It must be durable. Money must stand the test of time and the elements. It must not fade, corrode, or change through time. 2.) It must be portable. Money hold a high amount of 'worth' relative to its weight and size. 3.) It must be divisible. Money should be relatively easy to separate and re-combine without affecting its fundamental characteristics. An extension of this idea is that the item should be 'fungible'. Dictionary.com describes fungible as: "(esp. of goods) being of such nature or kind as to be freely exchangeable or replaceable, in whole or in part, for another of like nature or kind." 4.) It must have intrinsic value. This value of money should be independent of any other object and contained in the money itself.
'money, government'	An asset-backed debt instrument whose instances exist in universally understood quantities and which is 1) accepted as a medium of exchange 2) a store of value and 3) a standard of value. The backing asset must be alternatively available (in non-zero net supply) within the private sector. Essentially this means that money is a dual-use commodity.	The backing asset is either exists within the debt instrument itself (e.g., a copper coin) or is held by a custodian (e.g., a US Silver Certificate). Notes, certificates, greenbacks, assignats, bearer bonds, casino tokens, frequent flier miles, subway tokens, scrip, are not asset-backed and therefore not money. Mortgages ......
'currency'	Money which facilitates the transfer of goods and services	See ISO 4217 Currency codes.
'backing asset'	For money not self-backed, the specie or other asset to which the holder of money is entitled.	In addition to definitional attributes, a backing asset has several semi-definitional desiderata. It should be retrievable from its custodian at any time in any amount at minimal cost by any bearer of the money. There should be strict privacy with respect to any act of taking possession of the backing. The custodian must be highly trusted to have an unchanging and fully explicit policy and to never change this policy.
'base money'	the monetary liabilities of the sovereign. Real world base money today is currency (notes and coin which typically bear a zero nominal interest rate) plus commercial bank balances held with the central bank (which can be either interest-bearing or unremunerated). Base money can be created at essentially zero incremental cost by the government. Base money is an irredeemable final means of settlement for obligations of the government to the private sector.	This is evidently similar to or the same as monetary base, M0, narrow money, ... Buiter suggests “that (base) money is an asset to the private sector but not a liability to the public sector”. This is because base money is irredeemable. All liabilities of the sovereign (all money) are assumed to be issued by the central bank.
'outside money'	money that is either of a fiat nature (unbacked) or backed by some asset that is not in zero net supply within the private sector of the economy.	Outside money is a net asset for the private sector. The qualifier outside is short for (coming from) outside the private sector. Krugman has equated outside money with the monetary base.
'fiat' money	irredeemable base money which is legal tender.
'irredeemable'	an attribute of base money meaning that the central bank issuing it will do no better than offer new bank notes summing to the same denominated amount as those surrendered.	U.S and British currency is irredeemable. It is a little less clear that commercial bank balances held with the central bank, are irredeemable in the same sense.
'fiat'
'unbacked'

‘weak outside money’	money that is not a claim by one private agent on another private agent. The two most common forms of weak outside money are financial claims on the government held by the private sector, and various kinds of commodity money.	The qualifier outside is short for (coming from) outside the private sector. Gurley and Shaw introduced the inside money-outside money distinction in 1960.
'strong outside money'	weak outside money that is an asset to the consolidated private and public sectors
'commodity money'	strong outside money which is a quantity of a commodity.	The commodity may or may not have intrinsic (non-monetary) value as a consumption, intermediate or capital good. Gold, salt, cattle and cigarettes are historical examples having intrinsic value. Pet rocks, Samuelson's (1958) candy wrappers, and the stone money used on the Micronesian island state of Yap are examples without intrinsic value.
'self backed'	Money whose backing asset exists within the debt instrument itself.	Commodity money is self-backed. So is a fortune cookie, but the backing (the fortune) is not a commodity.
'inside money'	money that is a claim by one private agent on another private agent. money representing, or backed by, any form of private credit	The qualifier inside is short for (backed by debt from) inside the private sector. Since it is one private agent’s liability and at the same time some other agent’s asset, inside money is in zero net supply within the private sector.

US Federal Reserve notes carry the inscription: “This note is legal tender for all debts, public and private”.This is a short summary of the Section 102 of the Coinage Act of 1965 (Title 31 United States Code, Section 392), which contains the following text: " All coins and currencies of the United States, regardless of when coined or issued, shall be legal tender for all debts, public and private, public charges, taxes, duties and dues."

Buiter:

“...in the US, there is no Federal statute which mandates that private businesses or individuals must accept Federal Reserve notes or coin or Treasury notes as a form of payment. Private businesses are free to develop their own policies on whether or not to accept cash unless there is a State law which says otherwise.”

“This irredeemability property is clearly attached to currency issued by the government (generally through the central bank, although the US even today has Treasury notes outstanding). It is brought out very nicely in the phrase "...promise to pay the bearer the sum of ..." found on all Bank of England notes. It means that the Bank of England will pay out the face value of any genuine Bank of England note no matter how old. The promise to pay stands good for all time but simply means that the Bank will always be willing to exchange one (old) £10 Bank of England note for one (new) £ 10 Bank of England note (or even for two £ 5 Bank of England notes). Because it promises only money in exchange for money, this ‘promise to pay’ is, in fact, a statement of the irredeemable nature of Bank of England notes. It is less clear whether the second conventional component of base money, commercial bank balances held with the central bank, are irredeemable in the same sense as currency.

[See similar 1947 experiment with the US Dollar here.]

Commodity money such as gold coins – a gift from nature, perhaps with a little value added along the way – obviously represents net wealth to the economy as a whole, that is, to the consolidated private and public sectors.

Yap stone money differs from the fiat base money considered in this paper in two ways. First, the stock outstanding can be varied only very slowly (if at all) and at (prohibitively) high marginal cost. The monetary policy rules that rule out liquidity traps would be hard to implement in a world with Yap-style outside money. (This is perhaps just as well. A helicopter drop of Yap-style stone money could be a serious health hazard for those on the ground.)

Second, during any period, t, say, strong outside money of the intrinsically worthless Yap variety constitutes net wealth to the consolidated private and public sectors in an amount given by the period t value of the period t stock.

(Yap money shares this property with intrinsically valuable commodity money.)

As we shall see below, fiat base money issued by the government constitutes net wealth to the consolidated private and public sectors only in an amount given by the period t present discounted value of the terminal base money stock.

Non-Buiter:

Inside money	Any debt that is used as money. Is a liability to the issuer. Total amount of inside money in an economy is zero. (WkP)	Doesn't seem to agree with Buiter.
Outside money	money outside the monetary base. It is held in an economy in net positive amounts and is not anyone’s liability. Examples are gold or cash. (WkP)