Peer-reviewed and refereed are synonyms describing the same thing.
Peer-review is the process whereby an author's peers, who are experts in the same field, read and evaluate the author's article submitted for publication. This process is important in the decision about whether or not the article is published in the journal as written, with edits and modification or it is rejected. An article going through the peer-review process is called a refereed article.
Peer-reviewed/refereed articles are written for scholars in the field. Articles always have a list of references, generally have footnotes or in-text citations, may include tables, graphs or illustrations to support research, illustrations are in black & white with generally no color and they have few to no ads.