What does the prefix 'Tachy-' signify in medical terminology?

The prefix 'Tachy-' signifies something that is above normal or rapid, particularly in reference to heart rate or other physiological functions. In medical terms, it is commonly used to describe conditions such as tachycardia, which refers to a heart rate that exceeds the standard resting rate, typically over 100 beats per minute in adults. This prefix indicates an increased speed or elevated level, making it essential for understanding various medical conditions and their implications for patient care. In the context of medicine, differentiating between normal, slow, and elevated rates is crucial for diagnosis and treatment.