A review aggregator is a platform or website that collects and displays reviews from multiple sources for a particular product, service, or topic. These aggregators typically provide an overall rating based on the combined reviews, as well as snippets or summaries of individual reviews. Some popular review aggregators include Rotten Tomatoes for movies, Metacritic for video games, and Yelp for local businesses. These platforms can be helpful for consumers to quickly get an overview of opinions on a particular item before making a decision.