Radical 138 or radical stopping (艮部) meaning "stopping" or "stillness" is one of the 29 Kangxi radicals (214 radicals in total) composed of 6 strokes.

In Taoist Bagua cosmology, 艮 is the seventh of eight trigrams.

In the Kangxi Dictionary, there are just five characters (out of 49,030) to be found under this radical.

艮 is also the 146th indexing component in the Table of Indexing Chinese Character Components predominantly adopted by Simplified Chinese dictionaries published in mainland China.