The term 'stable sound' can be broken down into four crossword solutions: CLOP (4 letters), WHINNY (6 letters), SNORT (5 letters), and NEIGH (5 letters). All of these words refer to the sounds made by horses, which are commonly heard in a stable. CLOP is the sound of a horse's hooves hitting the ground, WHINNY is a high-pitched sound made by a horse, SNORT is a loud exhaling sound made by a horse, and NEIGH is a sound made by a horse to communicate with other horses.