Hmmmmm. Now that you bring it up ... when I was singing (for fun and profit) I would say :
"I have memorized the lyrics of that new song." However, when speaking about a song I might say "It has a beautiful lyric." -or- "The lyrics of that song are beautiful." -or even - "That new song has a beautiful lyric."
Make of it what you will!
Musick - where are you?