trefoil

From Middle English trefoil, borrowed from Old French trifoil, trefeul, from Latin trifolium, from tri- (“three”) + folium (“leaf”).

• IPA^(key): /ˈtɹɛ.fɔɪl/, /ˈtɹiː.fɔɪl/

trefoil (plural trefoils)

1. Any of several plants of the pea family, having compound, trifoliate leaves; especially one of the genus Trifolium.
2. A symbol having the shape of such leaves, especially when used as an architectural ornament.
   • New Historian, Ancient Pitcher Discovered in Historic Danish City, by David DeMar, 16 June 2015

     "The pristine, unbroken condition of the vessel – sometimes called a trefoil jug – caused the entire dig to 'come to a halt,' Søvsø remarked."

3. (topology) Ellipsis of trefoil knot

• quatrefoil
• cinquefoil
• sexfoil
• octofoil
• multifoil
• polyfoil

• bean trefoil

• loftier