The crossword solution for the term SLEEP SOUNDLY is SNORE, which is a five-letter word. Snoring is a common sound made by people while sleeping, usually caused by a partial obstruction of the airway. It can be a sign of sleep apnea, a disorder that causes people to stop breathing during sleep. Snoring can also be a sign of other medical conditions, such as allergies or sinus infections. People who SNORE often find it difficult to get a good night's sleep, so it is important to seek medical advice if snoring is a problem.