noun

1. any of a genus (Potentilla) of plants of the rose family, with white, yellow, or red flowers and fruit like a dry strawberry: some species have compound leaves with five leaflets arranged like the fingers on a hand
2. Archit. a circular design made up of five converging arcs

Etymology: ME cink foil < OFr cinquefoil < It cinquefoglie < L quinquefolium < quinque, five + folium, leaf: see foliate