A1C3T1I1N1I1D2E1S1
12 points
ACTINIDES is validvalid
ACTINIDE, any of a series of radioactive elements [n]
ACTINIDE, any element of a group from element number 89 (actinium) to 103 (lawrencium), also ACTINOID [n]
ACTINIDE, any of a series of radioactive elements [n]
ACTINIDE, any element of a group from element number 89 (actinium) to 103 (lawrencium), also ACTINOID [n]