scatter radiation
(SKA-ter RAY-dee-AY-shun)
Radiation that spreads out in different directions from a radiation beam when the beam interacts with a substance, such as body tissue. For example, during x-ray mammography, very small amounts of radiation may be scattered to areas away from the breast, such as the head and neck, sternum, and thyroid gland. The energy of scatter radiation is usually much lower than that of the original radiation beam.