trefoil

noun

tre·​foil ˈtrē-ˌfȯi(-ə)l  ˈtre- 

1

a

: clover sense 1

broadly : any of several leguminous herbs (such as bird's-foot trefoil) with leaves that have or appear to have three leaflets

b

: a trifoliolate leaf

2

: an ornament or symbol in the form of a stylized trifoliolate leaf

Illustration of trefoil

• trefoil 2

Examples of trefoil in a Sentence

Recent Examples on the Web

The brand’s trefoil logo is embroidered in gold at the forefoot, but the mule is otherwise blank in terms of outward branding. —Riley Jones, Footwear News, 18 Feb. 2026

The marble trefoil detail on the threshold of the shower evokes French-Moroccan architecture. —Blue Carreon, Forbes, 21 Feb. 2025

The British royal wore a petite diamond ribbon brooch, which features a ribbon design in a trefoil shape. —Julia Teti, WWD, 16 July 2024

The simplest torus knot — indeed, the simplest nontrivial knot, period — is called a trefoil. —Kevin Hartnett, Quanta Magazine, 5 Jan. 2024

Word History

Etymology

Middle English, from Anglo-French, from Latin trifolium, from tri- + folium leaf — more at blade

First Known Use

15th century, in the meaning defined at sense 1a

Phrases Containing trefoil

• bird's-foot trefoil
• tick trefoil

Rhymes for trefoil

• airfoil
• benzoyl
• despoil
• embroil
• etoile
• gargoyle
• recoil
• subsoil
• tinfoil
• topsoil
• turmoil
• aerofoil

Kids Definition

trefoil

noun

tre·​foil ˈtrē-ˌfȯil  ˈtref-ˌȯil 

1

: any of several herbs (as a clover) of the legume family with leaves that have or appear to have three leaflets

2

: an ornament or symbol shaped like a leaf with three parts