: someone or something that gathers together materials from a variety of sources
… an analyst at Morningstar, the Chicago-based aggregator of mutual fund statistics. John H. Christy, Forbes, 15 June 1998
… bloggers help enliven and expand public debate. They are indispensable aggregators of political news. Jonathan Alter, Newsweek, 28 July 2008
especially: a website or software application that aggregates information (such as news stories or website updates) from various Internet sources
RSS is an aggregator, a program that scans other websites that are also configured with RSS. It looks for key words or subjects, then downloads the content, so you don't have to spend the time surfing. Chris Taylor, Time, 30 May 2005