place, left village radical - 2 stroke form (no. 170)
阝 is a radical form used as a building block in other kanji, representing a place or village when on the left side. Its standalone meaning is tied to this radical role rather than an independent word.
阝 is a simplified radical form derived from 阜, which originally depicted a mound or hill and later came to represent a place or village in compound characters.
The shape looks like a stylized hill with a flat top and a slope, suggesting a raised place where a village might sit.
For こざと, imagine a small village (小里, こざと) nestled on the hill: こざと -> こざと, and the radical marks the place.