6 June 1944 vs Normandy landings

6 June 1944 and Normandy landings both are nouns.

Word	Noun	Adjective	Verb	Adverb
6 June 1944	Yes	No	No	No
Normandy landings	Yes	No	No	No

As nouns, 6 June 1944 and Normandy landings are synonyms defined as:

6 June 1944 and Normandy landings: date of the Allied landing in France, World War II

Other synonyms of 6 June 1944 include D-day.

6 June 1944 (noun)	Normandy landings (noun)
date of the Allied landing in France, World War II	date of the Allied landing in France, World War II