Carol Openers are a set of traditional Christmas carols that are often sung at the beginning of a Christmas celebration. The four carols that make up the Carol Openers are 'HARK' (4 letters), 'Adeste' (6 letters), 'Tis' (3 letters), and 'Bah' (3 letters), 'Ocome' (5 letters). These carols are often sung in Latin, but can also be sung in English. They are a popular way to start a Christmas celebration and bring joy to those who hear them.