広 is built from the 广 (house on a cliff) and ム (private) components.
It belongs to a phonetic family with 拡 and 鉱 — they share the 広 component and the reading コウ.
A common word using 広 is 背広 (せびろ), meaning “men's suit”.
Kanji that look similar include 庁, 庄, 床, and 序.