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Time and Frequency from A to Z, A to Z Notes

Unlike the glossaries produced by standards committees, Time and Frequency: From A to Z is not intended to be an official glossary of time and frequency terminology. Instead, this glossary was created as an educational tool. Like all technical fields, time and frequency has its own terminology and jargon, including terms that are seldom used outside the field, and terms that might have different meanings in other fields. Our goal was to produce a glossary of the most common terms in the time and frequency literature, and to provide the reader with a basic understanding of what those terms mean. Readers new to the field of time and frequency should find this glossary useful when reading papers such as those found in the NIST Time and Frequency Publication Database.

Time and Frequency: From A to Z was first published on-line in March 2002. The definitions in the original glossary were created by reviewing and combining material from a number of different sources, with the intent of producing consensus definitions that were complete, technically correct, and readable. Since then, the glossary has been revised based on the comments of readers, and we plan to continue to make changes to make the glossary more useful. Please email your comments, corrections, and suggestions to lombardi [at] (Michael Lombardi).

Created May 12, 2010, Updated September 26, 2016