The term 'BACK CHAIR' can be broken down into four crossword solutions: LYRE (4 letters), SPLAT (5 letters), SLAT (4 letters), and RECLINER (8 letters). A LYRE is a stringed instrument that has been used since ancient times. A splat is a sound made when something hits a surface with force. A SLAT is a thin, narrow strip of material, often used in furniture construction. Finally, a RECLINER is a type of chair that allows the user to lean back and relax. All of these terms are related to the term 'BACK CHAIR, ' which could refer to any type of chair that has a back support.