A plagiarizer is someone who uses the work or ideas of others without proper attribution or permission. Synonyms for this term include copycat, cheater, imitator, thief, fraudster, counterfeit, pilferer, and impostor. These individuals may claim credit for work they did not do, present ideas as their own, or use the work of others without citation. Plagiarism is considered a serious ethical breach in academic and professional settings, and can result in severe consequences such as legal action, loss of reputation, and even expulsion or termination. It is important to maintain integrity by properly citing and acknowledging the work of others, and actively avoiding plagiarism.