male sheep, ram
羝 centers on a male sheep, specifically a ram. The meanings are straightforward and refer to the same animal.
羝 combines 羊 (sheep) with 氐, which likely contributes the sound and may have originally depicted a ram or male animal. The exact historical development is uncertain.
The left side is a sheep 羊, and the right side 氐 looks like a sturdy base. Picture a ram with strong horns standing firmly on a rocky base.
For ラン, imagine a ram running across a field: run -> ラン, and the ram charges ahead.
ram (sheep)