A shamrock is a type of clover, used as a symbol of Ireland. Saint Patrick, one of Ireland's patron saints, is said to have used it as a metaphor for the Christian Holy Trinity. The name shamrock comes from Irish, which is the diminutive of the Irish word and simply means "young clover". At most times, Shamrock refers to either the species or Trifolium repens . However, other three-leaved plants—s... Wikipedia