curie (Ci) /kyo͝or″ē/ [Marie Skladowska Curie, Polish-born chemist and physicist, 1867–1934; Pierre Curie, French chemist and physicist, 1859–1906; both Nobel laureates] , (Obsolete) the non-SI unit used to measure the intensity of radioactivity in a material; the term was used before adoption of the SI unit, becquerel (Bq). One curie is equal to 3.70 × 1010 Bq.
