Final answer:
A brief in legal writing can refer to a short document that summarizes a legal argument or the full set of written arguments submitted by both parties in a legal case.
Step-by-step explanation:
A brief in legal writing has two meanings. The first is a short document that provides a summary of a legal argument. It is usually written by attorneys and is filed with the court to present the facts and arguments of a case. The second meaning of a brief is the full set of written arguments, including legal citations and authorities, submitted by both parties in a legal case. It is a comprehensive document that presents the arguments, relevant case law, and legal analysis to support each party's position.