Question: what does "merry go round" mean? 

Answer: "Merry" is to be happy or light hearted.  "Go round" is to go around.  A "merry go round" is a child's ride of horses or animals on a platform that slowly goes around in a circle and plays happy music.  It's fun, hence the term "merry go round."
This question from the Yahoo Q&A forum is categorized in the topic: Entertainment & Music