• Abnormal breathing where cycles of deep, labored breathing where cycles of deep, labored breathing are followed by cycles of weak breathing that can result in a total, temporary lack of airflow.
  Harvard Dictionary of Health Terms
  Harvard Medical Publishing, 2011
• An abnormal pattern of breathing characterized by alternating periods of apnea and deep, rapid breathing. The cycle begins with slow, shallow breaths that gradually increase in depth and rate and is then followed by a period of apnea. The period of apnea can last 5 to 30 seconds, then the cycle repeats every 45 seconds to 3 minutes.
  NLM Medical Subject Headings
  U.S. National Library of Medicine, 2025
• An abnormal pattern of respiration characterized by cycles of respiration that are increasingly deeper then shallower with possible periods of apnea. Affected patients may display a 10 to 20 second episode of hypoventilation or apnea, followed by respiration of increased depth and frequency over the course of about one minute. The cycle repeats every 45 seconds to 3 minutes.
  Human Phenotype Ontology (HPO)
  The Human Phenotype Ontology Project, 2025