trefoil

[ tree-foil, tref-oil ]

noun

1. any of numerous plants belonging to the genus Trifolium, of the legume family, having usually digitate leaves of three leaflets and reddish, purple, yellow, or white flower heads, comprising the common clovers.
2. any of various similar plants.
3. Architecture. an ornament composed of three lobes, divided by cusps, radiating from a common center.
4. such an ornamental figure used by the Girl Scouts as its official emblem.

adjective

1. of, relating to, or shaped like a trefoil.

trefoil

/ ˈtrɛfɔɪl /

noun

1. any of numerous leguminous plants of the temperate genus Trifolium , having leaves divided into three leaflets and dense heads of small white, yellow, red, or purple flowers
2. any of various related plants having leaves divided into three leaflets, such as bird's-foot trefoil
3. a leaf having three leaflets
4. architect an ornament in the form of three arcs arranged in a circle

Derived Forms

• ˈtrefoiled, adjective

Word History and Origins

Origin of trefoil¹

1350–1400; Middle English < Anglo-French trifoil < Latin trifolium triple leaf, the three-leaved plant, clover, equivalent to tri- tri- + folium leaf

Word History and Origins

Origin of trefoil¹

C14: from Anglo-French trifoil , from Latin trifolium three-leaved herb, from tri- + folium leaf

Example Sentences

This symmetry-matched strong field breaks the space and time symmetry within the material, and, more importantly, the resulting configuration depends on the orientation of the trefoil field with respect to the material.

From Science Daily

The trefoil also appeared on big travel bags, and as a print on trousers.

From Seattle Times

The steel-and-cement trefoil exploding from the earth resembles the Capitol from the Hunger Games films.

From Washington Post

In his luggage was the trefoil flag of a neo-Nazi hate group.

From Seattle Times

Bigwig followed Chervil along the run, down which came the scents of warm grass, clover and hop trefoil.

From Literature