CI

unit for measuring the amount of radioactivity

This is "see eye". For "see ell", see Cl. CI, Ci, ci, or cI (as a word, proper name and acronym) can refer to many things.
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.ci is the Internet country code top-level domain (ccTLD) for Côte d'Ivoire.
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CI cardiac index ; Colour Index. Ci curie. Ci abbr. curie CI abbr. color index Ci curie. See becquerel. CI 1 Cardiac index, see there 2. [more]Ci - Community and Resources

Noun
1. a unit of radioactivity equal to the amount of a radioactive isotope that decays at the rate of 37,000,000,000 disintegrations per second
(synonym) curie
(hypernym) radioactivity unit
(part-meronym) millicurie

Adjective
1. being one more than one hundred
(synonym) hundred and one, a hundred and one, one hundred one, 101
(similar) cardinal

CI, curie, unit for measuring radioactivity (named after Pierre Curie)