Scholarly journals contain articles that are peer-reviewed. What this means is the article was examined by a panel of experts in the same field before being published. These experts look for a set of criteria to determine the quality of the article and if the article disseminates new research.
However, not all scholarly journals are peer-reviewed. But all peer-reviewed journals are scholarly. Trade publications often contain scholarly articles that did not go through a review process. If in doubt, one resource to use to determine if the journal is a scholarly resource is to use the MLA Directory of Periodicals, Ebscohost's Serials Directory, and UlrichsWeb.