Some outward signs that a source is scholarly include that they:
Don't worry! You'll pick up a lot of this language as you advance in your major; as a beginner though, it can be useful to make a list of words you don't know as you read and then look them up in a tertiary source (like a dictionary.)
Scholarly journals are generally published at less frequent intervals—like biannually or quarterly—than magazines or newspapers. Unlike newspapers and magazines, scholarly journals do not attempt to report on what happened yesterday or today.
Probably the most important quality that makes a source scholarly is that it has been published by a scholarly publisher who uses a peer-review process to ensure the accuracy and originality of the content.