Which prefix means outside in medical terminology?

Which prefix means outside in medical terminology?

• A. Endo-
• B. Exo-
• C. Intra-
• D. Extra-

Answer: (B)

Exo- denotes outside or external, coming from Greek. It’s used when describing something located on or originating from the outside of a reference structure, such as exogenous substances or exoskeletons that sit on the outside. Endo- and intra- point to inside or within, and extra- means outside in a broader sense, but exo- is the precise prefix most often used to indicate outside relative to a given part. That’s why it’s the best choice for this question.

Exo- denotes outside or external, coming from Greek. It’s used when describing something located on or originating from the outside of a reference structure, such as exogenous substances or exoskeletons that sit on the outside. Endo- and intra- point to inside or within, and extra- means outside in a broader sense, but exo- is the precise prefix most often used to indicate outside relative to a given part. That’s why it’s the best choice for this question.