Conversation so far:
who plays the contrasting sections in a ritornello
In the Concerto Grosso, a ritornello structure was used, in which a recurrent section, or ritornello, alternates with episodes, or contrasting sections, played by the soloists.
In what kind of music are the ritornellos played
A ritornello is a recurring passage in Baroque music

Question: what is the meaning
Self-contained rewrite: What is the meaning of Baroque