NCI Dictionary of Cancer Terms

The NCI Dictionary of Cancer Terms features 8,440 terms related to cancer and medicine.

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electromagnetic spectrum
(ee-LEK-troh-mag-NEH-tik SPEK-trum)
The complete range of all types of radiation that has both electric and magnetic fields and travels in waves. The electromagnetic spectrum ranges from low-energy, low-frequency radiation that travels in long waves (such as radio waves and microwaves) to high-energy, high-frequency radiation that travels in short waves (such as x-rays and gamma rays).