These three words were concocted by one Curation service from a couple years ago. It's not clear whether the service ever developed a stable audience, but these words offer an interesting take on different aspects of curating the Internet.
Newsmastering is about searching, finding, aggregating, filtering, curating, editing, juxtaposing and publishing news content coming from the most disparate sources into one, highly thematic, content-specific news stream. (see Real-Time News Curation: NewsMastering and NewsRadars)
A NewsMaster is like a DJ. They do the above, using tools like RSS readers, to aggregate and filter the mass stream of data into a useful stream of information.
A NewsRadar is a web site that is a topic-specific news stream. It is a stream of news covering a very specific topic, event, product or person.
