Which root term means "center" in medical language?

The root term that means "center" in medical language is "centr/o." This combining form is derived from the Greek word "kentron," which translates to "center" or "hub." In medical contexts, it is frequently used in terms such as "centrifugal" (moving away from the center) and "concentric" (centered around a common point).

The other options refer to different anatomical or physiological concepts: "cerebr/o" relates specifically to the brain, "caud/o" pertains to the tail or tail-like structures, and "cephal/o" refers to the head. Each of these roots has its own distinct meaning and usage, which does not align with the definition of "center." Thus, "centr/o" is the appropriate choice when identifying the root that signifies a central point or position in medical terminology.