shamrock

/ˌʃæmˈrɑk/

/ˈʃæmrɒk/

Other forms: shamrocks

A shamrock is a three-leafed green clover that's used to symbolize Ireland. Go all out for St. Patrick's Day this year — decorate your whole house with shamrocks!

A clover must have exactly three leaves to be a shamrock, and some people believe only certain clover varieties qualify. Since at least 1675, Catholics have associated the shamrock with Saint Patrick, who famously used it to represent the Holy Trinity. It wasn't until the 18th century that it shifted from representing Ireland's patron saint to Ireland itself. The shamrock even shows up on some British coins, alongside the English rose and Scottish thistle.

Definitions of shamrock

1. noun

   clover native to Ireland with yellowish flowers; often considered the true or original shamrock
   synonyms: Trifolium dubium, hop clover, lesser yellow trefoil

   type of:

   clover, trefoil

   a plant of the genus Trifolium
2. noun

   creeping European clover having white to pink flowers and bright green leaves; naturalized in United States; widely grown for forage
   synonyms: Trifolium repens, dutch clover, white clover

   type of:

   clover, trefoil

   a plant of the genus Trifolium
3. noun

   Eurasian plant with heart-shaped trifoliate leaves and white purple-veined flowers
   synonyms: Oxalis acetosella, common wood sorrel, cuckoo bread

   type of:

   oxalis, sorrel, wood sorrel

   any plant or flower of the genus Oxalis