Identify the most appropriate antonym of the given word.
Summary

The correct answer is lengthy.

Step 1: Understand the meaning of the given word.
The word "Summary" refers to a brief statement or account that gives the main points of something, presenting information concisely without unnecessary detail.

Step 2: Understand the meanings of the given options.
• Abrupt: Sudden and unexpected, or brief to the point of rudeness.
• Lengthy: Continuing for a long time, overly detailed, or extended in duration and scope.
• Elliptical: Using or marked by extreme economy of words or ambiguity.
• Significant: Sufficiently great or important to be worthy of attention; meaningful.

Step 3: Identify the antonym.
Since a "summary" is concise and short, its direct opposite (antonym) is something that is long, detailed, and extended, which is defined by the word "lengthy".