plagiarizer

Etymology tree
Latin plagium
Proto-Indo-European *-yósder.
Proto-Italic *-āzijos
Latin -āriusnom.
Latin -ārius
Latin plagiārius
English plagiary
Proto-Indo-European *-id-
Proto-Indo-European *-yéti
Proto-Indo-European *-idyéti
Proto-Hellenic *-íďďō
Ancient Greek -ῐ́ζω (-ĭ́zō)bor.
Late Latin -izōder.
Middle French -iserbor.
Middle English -isen
English -ize
English plagiarize
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Latin -āriusbor.
Proto-Germanic *-ārijaz
Proto-West Germanic *-ārī
Old English -ere
Middle English -ere
English -er
English plagiarizer
From plagiarize + -er.