A1C3T1I1N1I1D2E1
11 points
ACTINIDE is validvalid
any of a series of radioactive elements [n ACTINIDES]
any element of a group from element number 89 (actinium) to 103 (lawrencium), also ACTINOID [n -S]
any of a series of radioactive elements [n ACTINIDES]
any element of a group from element number 89 (actinium) to 103 (lawrencium), also ACTINOID [n -S]