The term 'Holiday Song' can be broken down into two crossword solutions, 'CAROL' and 'NOEL'. 'CAROL' is a 5-letter word that is derived from the French word 'CAROLE', which means a dance accompanied by singing. It is also used to refer to a song of joy or celebration. 'NOEL' is a 4-letter word that is derived from the French phrase 'les bonnes nouvelles', which translates to 'the good news'. It is often used to refer to Christmas songs, particularly those that are sung during the holiday season. Both words are commonly used to describe festive holiday songs.