Any of a series of chemically similar, radioactive elements with atomic numbers ranging from 89 (actinium) through 103 (lawrencium).
A gaseous radioisotope of radon, formed by disintegration of actinium: at. no. 86; half-life of 3.92 seconds
Find another word for actinoid. In this page you can discover 2 synonyms, antonyms, idiomatic expressions, and related words for actinoid, like: actinide and actinon.