plagiariser vs plagiarizer

plagiariser and plagiarizer both are nouns.

Word	Noun	Adjective	Verb	Adverb
plagiariser	Yes	No	No	No
plagiarizer	Yes	No	No	No

As nouns, plagiariser and plagiarizer are synonyms defined as:

plagiariser and plagiarizer: someone who uses another person's words or ideas as if they were his own

Other synonyms of plagiariser include literary pirate, pirate, plagiarist.

plagiariser (noun)	plagiarizer (noun)
someone who uses another person's words or ideas as if they were his own	someone who uses another person's words or ideas as if they were his own