For you search query Reason we found around 2258 songs. We may show you only some of them on this page. Reason definition is - a statement offered in explanation or justification. How to use reason in a sentence. Synonym Discussion of reason. Reason is an American libertarian monthly magazine published by the Reason Foundation. The magazine has a circulation of around 50, and was named one of the 50 best magazines in 20by the Chicago seoptank.infoy: Reason Foundation.