What does R21 stand for?

What does R21 mean? This page is about the various possible meanings of the acronym, abbreviation, shorthand or slang term: R21.

Page 1 of our list of (R21) abbreviations features a selection of abbreviations relevant to various fields and disciplines, including governmental. One abbreviation that you will find on this page is R21, which is commonly used in the governmental industry. This list of abbreviations is intended to be a valuable resource for you as you work or study in these fields. Please feel free to refer back to this page whenever you come across an unfamiliar abbreviation, and check back frequently for updates as we continue to expand our collection.