Tax terms and acronyms can sometimes be confusing.  Here is a simplified list of many terms you may have heard and wondered about. 

AGI- Adjusted Gross Income

ATIN- Adoption Taxpayer Identification Number

DCN- Declaration Control Number – a number assigned to an electronic filing of a return (replaced by the Submission ID number for most returns as of the Tax Year 2011).

EFIN- Electronic Filing Identification Number

ETIN- Electronic Transmitter Identification Number

EIC- Earned Income Credit

EIN- Employer’s Identification Number

ERO- Electronic Return Originator

FICA- Federal Insurance Contributions Act

FIT- Federal Income Tax Withholding

ITIN- Individual Taxpayer Identification Number (used for alien status)

IRA- Individual Retirement Account

IRS- Internal Revenue Service

LES- Leave and Earning Statement (Military Pay Stub)

MACRS- Modified Accelerated Cost Recovery System (for depreciating items)

MAGI- Modified Adjusted Gross Income

MEF- Modernized e-Filing

MFJ- Married Filing Joint

MSA- Medical Savings Account

PDF- Portable Document File

PIN- Personal Identification Number

SEP- Simplified Employee Pension

SIMPLE- Savings Incentive Match Plans for Employees

SSN- Social Security Number

VITA- Volunteer Income Tax Assistance