阝 is a character used in Kangxi writing which serves as the combining form of two distinct radicals, distinguished by whether it is on the left or right of a character. It is the combining form of Radical 170

Radical 170

Radical 170 meaning "mound" or "dam" is 1 of 9 Kangxi radicals composed of 8 strokes.In the Kangxi Dictionary there are 348 characters to be found under this radical.- Characters with Radical 170:...

, 阜, when used on the left of a character, as in 阪, and of Radical 163

Radical 163

Radical 163 meaning "city" is 1 of 20 Kangxi radicals composed of 7 strokes.In the Kangxi Dictionary there are 350 characters to be found under this radical.- Characters with Radical 163:-See also:*...

, 邑, when used on the right of a character, as in 部.