small peak
巒 centers on a small mountain peak, specifically a pointed summit or a minor peak within a larger mountain range.
巒 combines 山 (mountain) with 䜌, which likely contributes the sound. The character is used for a small mountain peak.
The top 䜌 looks like a tangled, intricate shape, and the bottom 山 is a mountain. Picture a mountain range with many tangled peaks, and 巒 is one small, distinct peak among them.
For ラン, imagine a small peak you can run up: run -> ラン, and you dash to the top of the little mountain.
(mountain) peak; mountain; mountain range