We don't have synonyms for plagiarising yet — it may be a rare, specialized, newly coined, or misspelled word. The closest thesaurus entries we have are plagiarizing.
(v) :
Non-Oxford British English standard spelling of plagiarize. [(ambitransitive) To use, and pass off as one's own, someone else's writing, speech, ideas, or other intellectual or creative work, especially in an academic context; to commit plagiarism.]
(v) :
Non-Oxford British English standard spelling of plagiarize. [(ambitransitive) To use, and pass off as one's own, someone else's writing, speech, ideas, or other intellectual or creative work, especially in an academic context; to commit plagiarism.]