Is a song on a music album considered to be the titular song if it doesn't share the title of the album, but incorporates it into the lyrics? If not, is there another appropriate term for this lyrical gimmick?
According to TV Tropes, this is known as an "album title drop".
Although I'm surprised there's not a single word for it. Maybe you can make something up like "non-eponymous".
1.Holding or constituting a purely formal position or title without any real authority:
The queen is titular head of the Church of England
2.Nominally appointed to serve a diocese, abbey, or other foundation no longer in existence, and typically in fact having...
nominal - titulary
Date: 1500-1600 Language: Latin Origin: titulus
If you are worried for being inappropriate, use nominal for instance.