monopolizer vs monopoliser

monopolizer and monopoliser both are nouns.

Word	Noun	Adjective	Verb	Adverb
monopolizer	Yes	No	No	No
monopoliser	Yes	No	No	No

As nouns, monopolizer and monopoliser are synonyms defined as:

monopolizer and monopoliser: someone who monopolizes the means of producing or selling something

Other synonyms of monopolizer include monopolist.

monopolizer (noun)	monopoliser (noun)
someone who monopolizes the means of producing or selling something	someone who monopolizes the means of producing or selling something