n. 激进分子( radical的复数形式 ); 根基; 基本原理; [数学]根数

n. (chemistry) two or more atoms bound together as a single unit and forming part of a molecule

n. an atom or group of atoms with at least one unpaired electron; in the body it is usually an oxygen molecule that has lost an electron and will stabilize itself by stealing an electron from a nearby molecule

n. a person who has radical ideas or opinions