The term 'breathing problem during sleep' is often used to refer to a condition known as apnea, which is a 5-letter word. Apnea is a sleep disorder characterized by pauses in breathing during sleep, which can last from a few seconds to minutes. It is caused by the collapse of the upper airway, resulting in shallow or absent breathing. Symptoms of apnea include snoring, daytime sleepiness, and difficulty concentrating. Treatment for apnea includes lifestyle changes, such as avoiding alcohol and sleeping on one's side, as well as the use of continuous positive airway pressure (CPAP) machines.