Medical Definition of microcalcification
: a tiny abnormal deposit of calcium salts typically in the breast that is often benign but may be an indicator of breast cancer especially when appearing in compact clusters or a linear or branching pattern <A mammogram detects microcalcifications, which are tiny specks of calcium in the breast that may indicate cancer even before actual tumors form.—Andrew Weil, Self Healing, February 2008>
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