Cloverleaf

Part of speech: noun

Pronunciation: /ˈkləʊvəliːf/

Definitions

1. A road interchange that permits seamless vehicle transitions by using looped ramps in a design reminiscent of clover leaves
2. A layout resembling the leaves of a clover, employed in transportation to enhance traffic flow
3. A type of interchange design that utilizes curved ramps to facilitate smooth traffic movement, resembling the shape of clover leaves

Etymology: Cloverleaf is a plain compound: "clover" joined to "leaf," the two words combining to describe a shape that looks like a four-lobed clover leaf. The sense that matters most here is the transport one. Viewed from above, a cloverleaf interchange has loop ramps curving off the main roads in the pattern of a four-leaf clover, so the metaphor is visual rather than botanical. The botanical meaning came first. Clover leaves are typically trifoliate, which is why a four-leaf variant was once considered lucky, and the word "leaf" has long been used for the flat, broad organ of a plant. Applying that image to road layouts took a simple act of comparison, one that anyone looking down at a junction could make.

Synonyms: intersection, junction, crossing, interchange, overpass