Which combining form means yellow coloration?

• A. Xanth/o
• B. Calc/i
• C. Eti/o
• D. Phelb/o

Answer: (A)

In medical terminology, color is specified by combining forms derived from Greek or Latin roots. For yellow coloration, the form is xanth/o, coming from the Greek xanthos meaning yellow. This combining form appears in terms like xanthoderma (yellow skin), xanthochromia (yellow discoloration of body fluids such as cerebrospinal fluid), and xanthoma (yellowish plaques on the skin).

The other forms don’t denote color: calc/i relates to calcium or stones, eti/o to cause or etiology, and phelb/o to veins. Because they don’t convey yellow coloration, they aren’t the correct choice here.