1. Able to be trusted; dependable; consistently superior in quality: Mrs. Smart was a very reliable person who always arrived at work on time, kept up to date on her projects, and was always honest and truthful.

The washing machine was totally reliable and had never broken down!
2. Able to be trusted, to be accurate, and to provide correct information: The reports and facts given in the newspaper were always precise, true, and unfailingly reliable.