The term 'PODCAST SOURCE' can be solved by the 6-letter word 'ITUNES'. iTunes is a media player, media library, Internet radio broadcaster, and mobile device management application developed by Apple Inc. It is used to play, download, and organize digital audio and video on personal computers running the macOS and Microsoft Windows operating systems. It was first released in 2001 and is now available in over 100 countries. iTunes is also the primary way to manage the music and video content of Apple's popular iPod, iPhone, and iPad devices.