Brady- and Tachy- refer to which concept?

• A. Slow/fast
• B. Within
• C. Between two
• D. Against

Answer: (A)

Brady- and tachy- are prefixes that describe speed or rate in medical terms. Brady- means slow, as in bradycardia (slow heart rate) or bradypnea (slow breathing). Tachy- means fast, as in tachycardia (fast heart rate) or tachypnea (fast breathing). They indicate how quickly a process occurs, not where it happens or how many parts are involved. That’s why options about being within, between two, or against don’t fit—the prefixes specifically signal speed. The roots come from Greek, with brady- from bradys (slow) and tachy- from tachys (swift), helping you remember the meanings: slow versus fast.