any of a series of radioactive elements with atomic numbers 89 through 103
having a radial form;
"starfish are actinoid--that is, they are radially symmetrical"
This review summaries the application of ion exchangers in the separation and determination of alkali metals, alkali-earth metals, noble metals, rare earth elements and actinoid. 离子交换剂在萃取色谱中得到了广泛的应用，本文详细总结了离子交换剂在分析化学中用于碱金属、碱土金属、贵金属、稀土元素、锕系元素等的分离与测定。
The problem of collecting and delivery shunting of non-through wagon flow on the actinoid private line belongs to a kind of the combinatorial optimization problems. 放射形专用线非直达车流取送车问题属于一类组合优化问题,影响因素较多。
starfish are actinoid--that is, they are radially symmetrical. 海星呈放射性形状－那就是说，他们是呈对称的放射状。