universal time vs Greenwich Time

universal time and Greenwich Time both are nouns.

Word	Noun	Adjective	Verb	Adverb
universal time	Yes	No	No	No
Greenwich Time	Yes	No	No	No

As nouns, universal time and Greenwich Time are synonyms defined as:

universal time and Greenwich Time: the local time at the 0 meridian passing through Greenwich, England; it is the same everywhere

Other synonyms of universal time include GMT, Greenwich Mean Time, UT1, UT.

universal time (noun)	Greenwich Time (noun)
the local time at the 0 meridian passing through Greenwich, England; it is the same everywhere	the local time at the 0 meridian passing through Greenwich, England; it is the same everywhere