trefoil

American  

[tree-foil, tref-oil] / ˈtri fɔɪl, ˈtrɛf ɔɪl /

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.

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adjective

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

trefoil British  

/ 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

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Other Word Forms

• trefoiled adjective

Etymology

Origin of trefoil

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

Example Sentences

They superimposed these fields onto each other, so that the total polarization in time traced the desired trefoil shape.

From Science Daily • Apr. 24, 2024

The collaboration included men’s suits in track-worthy shades of royal blue and purple with the Adidas stripes down the sleeves and trousers and Gucci written under sports brand’s trefoil.

From Seattle Times • Feb. 25, 2022

The butterfly may thrive in active quarries because its egg-laying plant of choice, birdsfoot trefoil, grows well in the parts that aren’t being excavated, Fartmann says.

From Science Magazine • Nov. 18, 2021

It was to be a 42-story, billion-dollar resort featuring “an exotic South Seas theme,” a swim-up shark exhibit and a trefoil footprint with a facade of gold leaf.

From Washington Post • Oct. 5, 2017

After a glance round among them Holly went up to Silver, who was feeding with Fiver in a patch of yellow trefoil.

From "Watership Down: A Novel" by Richard Adams