gasbag vs dullard

gasbag and dullard both are nouns.

Word	Noun	Adjective	Verb	Adverb
gasbag	Yes	No	No	No
dullard	Yes	No	No	No

As nouns, dullard is a hypernym of gasbag; that is, dullard is a word with a broader meaning than gasbag:

Other hypernyms of gasbag include bore.

gasbag (noun)	dullard (noun)
the bag containing the gas in a balloon	a person who evokes boredom
a boring person who talks a great deal about uninteresting topics	a person who is not very bright