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Phrases starting with the letter: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

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Definition of: acpetinium

(ak·tinē·əm) noun
A short-lived radioactive element (symbol Ac, atomic number 89), occurring naturally in uranium and radium ores and produced synthetically in nuclear reactors, the most stable isotope having an atomic mass of 227 and a half-life of 21.6 years. See PERIODIC TABLE.

Phrases starting with the letter: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

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