Radical 2

Radical 2 or radical line meaning "vertically connected" is one of 6 of the 214 Kangxi radicals that are composed of only one stroke.
In the Kangxi Dictionary, there are only 21 characters to be found under this radical.
丨 is also the 2nd indexing component in the Table of Indexing Chinese Character Components predominantly adopted by Simplified Chinese dictionaries published in mainland China, with 亅 being its associated indexing component.

In calligraphy

The only stroke in radical line, known as 豎/竖/竪 shù "vertical", is called 努 nǔ in the eight principles of the character 永 which are the basis of Chinese calligraphy.

Literature

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