quatrefoil

noun2

1. •
   A symmetrical shape that forms the overall outline of four partially-overlapping circles of the same diameter.

   • It was a narrow, gravelled island we had to lie on, guarded by glazed brick chimneys and, running along the sides, a prickly little gothic fence of iron finials and terracotta quatrefoils. — 1988
2. •
   A stylized flower or leaf with four lobes.