morning vs word of farewell

morning and word of farewell both are nouns.

Word	Noun	Adjective	Verb	Adverb
morning	Yes	No	No	No
word of farewell	Yes	No	No	No

As nouns, word of farewell is a hypernym of morning; that is, word of farewell is a word with a broader meaning than morning:

morning: a conventional expression of greeting or farewell, used to wish someone a good morning
word of farewell: an acknowledgment or expression of goodwill at parting

Other hypernyms of morning include farewell, greeting, salutation.

morning (noun)	word of farewell (noun)
a conventional expression of greeting or farewell, used to wish someone a good morning	an acknowledgment or expression of goodwill at parting
the earliest period
the time period between dawn and noon
the first light of day