ruševina

1. ruin; ruins; rubble
   Posle zemljotresa grad je bio u ruševinama. — After the earthquake the city was in ruins.
   Spasioci su izvukli ženu ispod ruševina. — Rescuers pulled a woman out from under the rubble.
2. (of a building) a wreck; a derelict building
   Kupili su staru ruševinu na selu i renovirali je. — They bought an old wreck of a house in the village and renovated it.

In the sense "ruins" it is mostly used in the plural: ruševine.