Namul 나물 includes also Che 채 and Muchim 무침 which often overlap and called interchangeably. Muchim usually means a fresh green that's tossed in a spicy dressing whereas a Che refer to dishes that often involve a mix of julienned vegetables.
Kongnamul Muchim (Soybean Sprouts), Gaji Namul (Steamed Eggplant), Samsaek Namul (Three color namul) are some great dishes to try.