Superseer (Spanish for, “to discontinue; cease”) comes from the Latin supersedere which in term is a combination of the prefix super- (“above”) and sedere (“to sit”). When you stop doing something — you’re now, literally, sitting on top of it. At least in Spanish.

From the Latin sedere root, we get various English words related to sitting, including:

From the same Latin root sedere we also get the Spanish… asiento, the common word for, seat. Now that makes sense, doesn’t it?

The s‑n-t/d root is visible in most of these words. Note that in superseer, the middle ‑n- disappeared: hence the ‑e- on both sides!