What does the medical root 'lith' mean?

• A. Stone
• B. Rock
• C. Crystal
• D. Mineral

Answer: (A)

lith denotes stone. The root comes from Greek lithos meaning stone, and in medical language it signals a stone or calculus formed in the body or targeted by treatment. That’s why you see terms like nephrolithiasis (kidney stones) and cholelithiasis (gallstones), as well as lithotripsy (crushing stones) and lithotomy (removal of stones). The other options don’t fit because rock, crystal, and mineral describe broader solid materials, not the specific sense of a stone or calculus used in medical terminology.