1. Radical refers to a certain part obtained after cutting the combined character. In the past, the left side of a combined character was called "bia" and the right side was called "side"; now the components of a combined character are collectively called "radicals". If it is located on the left side of the word, it is called "left radical"; if it is located on the right side of the word, it is called "right radical".

2. Radicals are character category headings determined by dictionaries and dictionaries in order to classify Chinese characters. They are generated from analyzing the structure of fonts. Radicals are radicals that have the function of classifying fonts and are the first characters of each radical in the calligraphy book. There are two types of radicals with different properties: one is based on the principle of character creation (philology), which strictly follows the Six Books system. Only characters with the same meaning can belong to the same radical. The other is the radical based on the character search method. It is based on the glyph structure and takes the same parts as the basis for character search, and arranges them in parts. The same parts are called radicals.

Extended information:

Evolution of radicals:

Some components that often appear in Chinese character shapes. For example: the "任" in "position, residence, jian, stop", the "囗" in "guo,gu,quan,wei", the "bia" in "bia,pian,pian,bian" are all radicals. .

In the traditional theory of Chinese character structure, Chinese characters are divided into two types: single characters and combined characters according to their constituent units. Single characters (sun, moon, cow, sheep, upper, lower, etc.) are composed of strokes, while combined characters (xiu, que, she, sen, pole, frame, etc.) are composed of radicals. Therefore, radicals are a name in the traditional Chinese character structure theory, which refers to the components of the meanings and pictophonetic characters in the "Six Books", or represent meanings or sounds.

For example, the "任" and "木" in "xiu", the "er" and "you" in "take", the "jia" and "木" in "jia", etc. Radicals are composed of strokes and are one level higher than strokes. Radicals can also be classified according to different criteria. For example, whether it is a word, whether it is compound and can be divided into other parts, etc.

The six-book analysis method is no longer fully applicable to modern Chinese characters. Therefore, the academic community of philology has constructed a new system for structural analysis of Chinese characters. This system is: strokes-parts-whole characters. The difference from the previous one is that the new system proposes "parts".

Reference materials: Baidu Encyclopedia - Radicals? Baidu Encyclopedia - Radicals