The combining form radi/o means
A Radical
B Radial
C Radar
D Radiation
The correct answer and explanation is:
The correct answer is D) Radiation.
Explanation:
The combining form radi/o is derived from the Latin word radius, meaning “ray” or “spoke of a wheel.” In medical and scientific terminology, radi/o is commonly used to refer to radiation, which is the emission or transmission of energy in the form of waves or particles through space or a material medium.
Here’s a breakdown of why radi/o means radiation and why the other options don’t fit as well:
- A) Radical: The term “radical” generally means something fundamental or extreme, or in chemistry, a group of atoms with unpaired electrons. It does not connect to the combining form radi/o.
- B) Radial: Radial relates to radius or rays extending from a central point. While this has a connection to radius, radi/o as a combining form is more specifically associated with radiation rather than simply “radial.” The term “radial” itself uses “radi-” as a root but is not the direct meaning of the combining form.
- C) Radar: Radar is an acronym for “Radio Detection and Ranging” and is unrelated to the combining form radi/o.
- D) Radiation: This is the correct choice. In medical terms, words like radiology (the study and use of medical imaging techniques using X-rays or other radiation) and radiotherapy (treatment using radiation, usually for cancer) use the combining form radi/o to indicate the involvement of radiation.
Additional Context:
In English medical and technical vocabulary, the combining form radi/o often relates to rays or radiation, especially electromagnetic radiation such as X-rays or gamma rays. It is widely used in various words such as:
- Radiology – the branch of medicine that uses imaging techniques like X-rays.
- Radiotherapy – treatment using controlled doses of radiation.
- Radioactive – the property of certain substances to emit radiation.
Thus, radi/o is firmly associated with radiation, making option D the correct answer.