1. the quality or state of being easily excited or stimulated; tendency to become aroused or agitated
Usage: commonly used in psychology, neurology, and general contexts
2. in physiology and neuroscience, the capacity of a nerve or muscle to respond to a stimulus
Usage: technical; used in medical and biological contexts

Examples

• The child's excitability made it difficult for her to sit still during the long lecture.
• His nervous excitability increased as the exam date approached.
• The medication helped reduce the patient's excitability and mood swings.
• Caffeine can increase excitability in the nervous system.
• Her natural excitability meant she was always eager to try new activities.
• The doctor noted the infant's excitability as a normal developmental response.
• Stress tends to heighten emotional excitability in most people.