(DoD) A measure of time that conforms, within a close approximation, to the mean diurnal rotation of the Earth and serves as the basis of civil timekeeping. Universal Time (UT1) is determined from observations of the stars, radio sources, and also from ranging observations of the moon and artificial Earth satellites. The scale determined directly from such observations is designated Universal Time Observed (UTO); it is slightly dependent on the place of observation. When UTO is corrected for the shift in longitude of the observing station caused by polar motion, the time scale UT1 is obtained. When an accuracy better than one second is not required, Universal Time can be used to mean Coordinated Universal Time. Also called ZULU time. Formerly called Greenwich Mean Time.
Department of Defense Dictionary of Military and Associated Terms. 31 January 2011.
| APA | Military Dictionary (DoD). (2011). universal time. Retrieved September 22, 2026, from http://smartdefine.org/universal_time/definitions/1959856 |
| Chicago | Military Dictionary (DoD). 2011. "universal time" http://smartdefine.org/universal_time/definitions/1959856 (accessed September 22, 2026). |
| Harvard | Military Dictionary (DoD) 2011, universal time, Smart Define, viewed 22 September, 2026, <http://smartdefine.org/universal_time/definitions/1959856>. |
| MLA | Military Dictionary (DoD). "universal time" 4 April 2011. Web. 22 September 2026. <http://smartdefine.org/universal_time/definitions/1959856> |