The word "song"

I'm interested in what appears to be a shift in the way the word "song" is used.  The traditional definition of "a short piece of music with words" seems to be being replaced by "any piece of music" in some contexts/quarters.  So, I'm interested in how respondents define and use the word.  So for each of a selection of different types of music I want to ask "does $pieceofmusic" fit your definition of song?" and "would you use the sentence $piece of music is a song by $person?"

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* 1. Which of the following fit your  definition of a song?

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* 2. For which of the following would you the sentence "$Pieceofmusic is a song (by $person)"?

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* 3. Any other thoughts?

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