阝 ( Kangxi radical 163 & 170) 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 ( 阜) when used on the left of a character, as in 阪, and of Radical 163 ( 邑) when used on the right of a character, as in 部.
In Unicode, ⻖ (U+2ED6) is listed as CJK RADICAL MOUND TWO [1] (meaning 阜 - left) and ⻏ (U+2ECF) is listed as CJK RADICAL CITY [2] (meaning 邑 - right). Most, but not all, [3] fonts render them as almost identical. 阝 (U+961D), listed as CJK UNIFIED IDEOGRAPH-961D, [4] is usually used to represent both.