fuddy-duddy vs conservativist

fuddy-duddy and conservativist both are nouns.

Word	Noun	Adjective	Verb	Adverb
fuddy-duddy	Yes	No	No	No
conservativist	Yes	No	No	No

As nouns, conservativist is a hypernym of fuddy-duddy; that is, conservativist is a word with a broader meaning than fuddy-duddy:

fuddy-duddy: a conservative who is old-fashioned or dull in attitude or appearance
conservativist: a person who is reluctant to accept changes and new ideas

Other hypernyms of fuddy-duddy include conservative.

fuddy-duddy (noun)	conservativist (noun)
a conservative who is old-fashioned or dull in attitude or appearance	a person who is reluctant to accept changes and new ideas