1. superlative form of buff; most muscular or physically fit
Usage: informal; often used in casual or slang contexts
2. superlative form of buff; most knowledgeable or expert about a particular subject
Usage: informal; often used to describe an enthusiast or expert

Examples

• He's the buffest guy at the gym after months of training.
• She became the buffest member of the team through dedicated weightlifting.
• He's the buffest Star Wars buff in the entire fan community.
• The buffest athletes on campus always attract attention.
• After a year of consistent workouts, he was the buffest he'd ever been.
• She's the buffest film buff I know—she can quote any classic movie.