The central six-membered ring in the title compound, C(16)H(16)O(3), is almost planar (and almost coplanar with the aromatic ring), despite one of its C atoms being formally sp(3) hybridized. The planarity is a consequence of the C atom at the centre of the spirocyclic system also being part of the three-membered epoxide ring. The molecules are linked by pi-pi and C-H.pi interactions.