- AKA Greenwich Mean Time (GMT).
Simply another way to express Greenwich Mean Time. Used in radio traffic and expressed using the 24-hour clock. For example, 1700 ZULU denotes 5pm at the Royal Observatory in Greenwich, London.
There’s a very long history regarding the use of time and the need for accurate chronometers in seafaring. Effective navigation relied on the development of accurate (and portable) timepieces, among other things, to allow mariners to calculate their latitude.
Crowell, J. (2003, October 31). Naval Terminology, Jargon and Slang FAQ Part 2 – N through Z. Retrieved from http://www.hazegray.org/faq/slang2.htm