Final answer:
Stridor is a high-pitched, wheezing sound caused by disturbed airflow, often requiring medical attention. It can also be used metaphorically in literature to describe similarly harsh sounds.
Step-by-step explanation:
The term stridor refers to a high-pitched, wheezing sound caused by disrupted airflow. Stridor may occur due to various conditions that cause narrowing or obstruction of the upper airway. Sounds like these can be a critical indicator of respiratory distress and warrant immediate medical evaluation.
A notable example of stridor can be found with the infection known as pertussis, or whooping cough, particularly in infants. The distinctive 'whooping' sound associated with pertussis is a classic example of stridor. However, not all instances of stridor are related to infections; they can also be a symptom related to physical obstructions, allergic reactions, or other causes of airway compromise.
In literature and descriptive language, stridor is also used metaphorically to describe harsh, grating or creaking sounds, much like the one described as 'Oldring's knell' in the provided excerpt. This figurative use of stridor enriches the narrative by evoking a sensorial experience of harsh and jarring noise.