a wall or jetty built out from a riverbank or seashore to control erosion Also called spur, breakwater
Word Origin
C16: origin uncertain: perhaps altered from groin
Word Origin and History for groyne
n.
"strong, low sea wall," 1580s, perhaps from obsolete groin "pig's snout" (c.1300; the wall so called because it was thought to look like one), from Old French groin, from Latin grunnire "grunt."