hotdog vs show-off

hotdog and show-off both are nouns.

Word	Noun	Adjective	Verb	Adverb
hotdog	Yes	No	No	No
show-off	Yes	No	No	No

As nouns, show-off is a hypernym of hotdog; that is, show-off is a word with a broader meaning than hotdog:

hotdog: someone who performs dangerous stunts to attract attention to himself
show-off: someone who deliberately behaves in such a way as to attract attention

Other hypernyms of hotdog include exhibitionist.

hotdog (noun)	show-off (noun)
a smooth-textured sausage of minced beef or pork usually smoked; often served on a bread roll	someone who deliberately behaves in such a way as to attract attention
a frankfurter served hot on a bun
someone who performs dangerous stunts to attract attention to himself