rubbernecker vs spectator

rubbernecker and spectator both are nouns.

Word	Noun	Adjective	Verb	Adverb
rubbernecker	Yes	No	No	No
spectator	Yes	No	No	No

As nouns, spectator is a hypernym of rubbernecker; that is, spectator is a word with a broader meaning than rubbernecker:

rubbernecker: a person who stares inquisitively
spectator: a close observer; someone who looks at something (such as an exhibition of some kind)

Other hypernyms of rubbernecker include looker, viewer, watcher, witness.

rubbernecker (noun)	spectator (noun)
a person who stares inquisitively	a woman's pump with medium heel; usually in contrasting colors for toe and heel
	a close observer; someone who looks at something (such as an exhibition of some kind)