As per ProQuest, a peer reviewed journal can be defined as:
A publication in which articles go through an official editorial process that involves review and approval by the author's peers (people who are experts in the same subject area). Most (but not all) scholarly publications are peer reviewed. Some trade publications are peer reviewed.
For more information on peer reviews (blind, open, etc.) visit the following sites:
You can search the article in Search Me and apply the peer reviewed filter. If the article remains in the result list, it should be peer reviewed.
You can look up the journal where the article is published and check if it is a peer reviewed journal. The publisher’s website should indicate if the journal articles go through a peer review process (please note that not everything from a peer reviewed journal is peer reviewed, for example, literature reviews and editorials are not peer reviewed. Peer reviewed articles should contain an abstract introducing its original research and a long list of references).