As nouns the difference between archnemesis and archrival
is that archnemesis is a chief {{l/en|nemesis}} while archrival is a chief rival.
archnemesis
Noun
(archnemeses)
A chief .
Synonyms
* archenemy
* archfoe
* archvillain archrival
English
Alternative forms
* arch rival, arch-rival
Noun
(
en noun)
A chief rival.
- The New York Yankees are playing their archrival the Boston Red Sox tonight.
Usage notes
Generally applied only to rivals who have competed against each other for at least a few years.
Synonyms
* (l)