The crossword solution for the term 'confessional' is 'SIN', which is a three-letter word. Confession is the act of admitting one's wrongdoings or sins to a higher power, usually a religious figure such as a priest or pastor. It is a practice that has been around since ancient times and is still practiced in many religions today. Confessionals are small booths or rooms where people can go to confess their sins in private.