Peer review is a process where scholars or scientists (“peers”) evaluate the quality of other scholar's work before it is published in a journal.
The peer review process--also called refereed--ensures rigor, novelty, correctness and consistency; it is one of the gold standards of science.
Image source: Editage Insights.
Is it peer-reviewed? The Serials Directory can provide you with this information.
Or you can ask a librarian. We're always happy to help.