A phrase is a group of words that does not contain both a subject and a predicate, and therefore does not express a complete thought on its own. A dependent clause, on the other hand, is a group of words that contains both a subject and a predicate but cannot stand alone as a complete sentence because it relies on an independent clause to form a complete thought. In other words, a dependent clause is a type of clause, whereas a phrase is not a clause at all.
