More than 10,000 abbreviations, acronyms, and initialisms are included in alphabetical lists compiled from documents prepared by contributing editors of the Communications Services organization at the Y-12 National Security Complex and other staff members of the Oak Ridge National Laboratory, the former Oak Ridge K-25 Site, and Y-12 in Oak Ridge, Tennessee.

To find an acronym, initialism, or abbreviation from our site, use the Search for Acronyms page.

If you cannot find what you are looking for, send a message asking to have the acronym and its definition added to our list. Please identify your relationship with one of the Oak Ridge DOE contractors.

The following definitions are offered for abbreviation, acronym and initialism as used on this website.

  • An abbreviation is a shortened form of a word or a phrase used in place of the word or phrase in which only the letter(s) are pronounced (e.g., NRC for Nuclear Regulatory Commission). An abbreviation may be formed from just the initial letter of a word (e.g., J for joule); some of the initial letters of a phrase (e.g., UT for The University of Tennessee); or all of the initial letters of a phrase (e.g., TVA for Tennessee Valley Authority). Although the abbreviations of chemical elements and units of measurement are called symbols, they are often referred to in this document as abbreviations.
  • An acronym is a pronounceable word formed from more than just the initial letters of each of the successive parts or major parts of a compound term (e.g., radar is the acronym of radio detecting and ranging).
  • An initialism is an acronym (pronounceable word) formed from only the initial letters of the major words in a compound term (e.g., NASA is the initialism of National Aeronautics and Space Administration).