M

Marginal Tax Rate
The tax rate that applies to the last dollar of income earned.
Married Filing Jointly
A filing status claimed by married couples who wish to combine income and file a single tax return together in order to take advantage of various tax benefits.
Married Filing Separately
A filing status claimed by married couples who do not wish to file a joint return and agree to report their income separately.
Mortgage
A loan made to purchase property, generally real estate. The borrower pledges the property to the lender as collateral to guarantee repayment of the loan.
Medical Savings Account (MSA)
See Archer Medical Savings Account.
Multiple Support Agreement
When two or more taxpayers who provide financial support for a particular person agree to officially designate that person as the dependent of one of the supporting taxpayers, to allow that taxpayer to claim dependency exemptions and various credits and deductions.