阻 is built from the 阝 (hill (left) / village (right)) and 且 components.
It reads ソ like 且, as do 組, 祖, 粗, and 租 — learn 且 once and the family's reading comes with it.
A common word using 阻 is 阻止 (そし), meaning “obstruction, check, hindrance”.
Kanji that look similar include 邪, 邸, 阿, and 那.
