Manipulation - An illegal operation. Buying or selling a security for the purpose of creating false or misleading appearance of active trading or for the purpose of raising or depressing the price to induce purchase or sale by others.

Margin - The amount paid by the customer when using a broker's credit to buy or sell a security. Under Federal Reserve regulations, the initial margin requirement since 1945 has ranged from the current rate of 50% of the purchase price up to 100%.

Margin call - A demand upon a customer to put up money or securities with the broker. The call is made when a purchase is made; also if a customer's account declines below a minimum standard set by the exchange or by the firm.

Market order - An order to buy or sell a stated amount of a security at the most advantageous price obtainable after the order is represented in the trading crowd.

Market price - The last reported price at which the stock or bond sold, or the current quote.

Maturity - The date on which a loan or bond comes due and is to be paid off.

M&E charges - These are mortality and expense risk charges on variable annuities that compensate the insurance company for the risk that you will live longer than your life expectancy. They typically are about 1.25 percent per year of your account value.

Medicaid - A joint federal/state program that pays for health care for individuals and families with low incomes or very high medical bills relative to their income and assets. Coverage and eligibility requirements vary from state-to-state. Medicaid is the primary payer of nursing home care. Some states also offer some home and community-based long-term care services for eligible individuals through their Medicaid programs. These additional services are at the option of the state and are not mandated by federal law.

Medi-Cal - California's Medicaid program.

Medicare - The federal program that provides hospital and medical care to people age 65 or older, and to some younger people who are very ill or disabled. Benefits for nursing home and short-term home health services are limited and are generally available only to people while they are recovering from an acute illness. Coverage is restricted to medical care, and does not include custodial care at home or in nursing homes.

Medicare Supplement Insurance - A private insurance policy that covers many of the gaps in Medicare coverage (also known as Medigap Insurance or Medicare Supplemental Insurance). Except in Minnesota, Massachusetts and Wisconsin, there are 12 standardized plans labeled Plan A through Plan J. (Not all insurance companies offer all 12 plans.) Medicare Supplement Insurance policies work only if you are enrolled in the Original Medicare Plan. But, they won't pay any benefits if you are enrolled in a Medicare HMO or another type of Medicare Plus plan. Medicare Supplement policies can minimize Medicare copayments and deductibles for covered services, but generally do not offer expanded coverage such as long-term care services or prescription drugs.

Medigap - See Medicare Supplement Insurance.

Member corporation - A securities brokerage firm, organized as a corporation, with at least one member of the New York Stock Exchange who is an officer or employee of the corporation.

Member firm - A securities brokerage firm organized as a partnership and having at least one general partner or employee who is a member of the New York Stock Exchange.

Member organization - The term includes New York Stock Exchange member firms and member corporations.

Merger - Combination of two or more corporations.

Mid-Cap - A stock with a medium level of capitalization, usually between $1 billion and $5 billion in market value (market value = price per share multiplied by number of shares outstanding).

Midgets - A slang term referring to a Government National Mortgage Association (GNMA) bond, which has a 15 year maturity. The midget is secured by mortgages backed by federal agencies. GNMA is also known as "Ginnie Mae".

Minimum Distribution - The minimum annual required distribution amount for an IRA holder reaching age 70 1/2; also called Required Minimum Distribution (RMD).

Money market fund - A mutual fund whose investments are in high-yield money market instruments such as federal securities, CDs and commercial paper. Its intent is to make such instruments, normally purchased in large denominations by institutions, available indirectly to individuals.

Money Purchase Plan - A money purchase plan requires set annual contributions from the employer to individual accounts and is subject to other rules.

Morningstar Rating for Funds - A proprietary system that rates mutual funds from 1 to 5 stars based on how well they have performed (after adjusting for risk and accounting for sales charges) in comparison to similar funds. Within each Morningstar Category, the top 10% of funds receive 5 stars; the bottom 10% receive 1 star. Funds are rated for up to three time periods: 3, 5, and 10 years; these ratings are then combined to produce an overall rating. Funds with less than three years of history are not rated. Ratings are objective, based entirely on a mathematical evaluation of past performance. They're a useful tool for identifying funds worthy of further research, but shouldn't be considered buy or sell signals.

Mortgage bond - A bond secured by a mortgage on a property. The value of the property may or may not equal the value of the bonds issued against it.

Mortgage REIT - A REIT (Real Estate Investment Trust) that invests in loans secured by real estate. The REIT earns its income from mortgage interest and fees.

Multiemployer Plan - A retirement plan sponsored by several employers under collective bargaining agreements that meets certain other requirements. A participant who changes jobs from one sponsoring employer to another stays within the same plan.

Municipal bond - A bond issued by a state or a political subdivision, such as county, city, town or village. The term also designates bonds issued by state agencies and authorities. In general, interest paid on municipal bonds is exempt from federal income taxes and state and local taxes within the state of issue. However, interest may be subject to the alternative minimum tax (AMT).