The phrase "for a song" means to obtain or purchase something for an extremely low price, often much less than its actual value. It is used figuratively to describe getting something easily or with little effort.
Sentences with «for a song»
You don't have to watch actors ham it up, instead the music videos for each song play in the background. (gimmegimmegames.com)
Picking the best rewards card for you can feel like searching for a song in a digital music store when you don't know the name of it. (creditdonkey.com)
As I explored the beauty in our parks, I invented new lyrics for these songs. (parksconservancy.org)