fire watching vs civil defense

fire watching and civil defense both are nouns.

Word	Noun	Adjective	Verb	Adverb
fire watching	Yes	No	No	No
civil defense	Yes	No	No	No

As nouns, civil defense is a hypernym of fire watching; that is, civil defense is a word with a broader meaning than fire watching:

fire watching: (during World War II in Britain) watching for fires started by bombs that dropped from the sky
civil defense: activities organized by civilians for their own protection in time of war or disaster

fire watching (noun)	civil defense (noun)
(during World War II in Britain) watching for fires started by bombs that dropped from the sky	activities organized by civilians for their own protection in time of war or disaster