<P> A shamrock is a young sprig, used as a symbol of Ireland . Saint Patrick, Ireland's patron saint, is said to have used it as a metaphor for the Christian Holy Trinity . The name shamrock comes from Irish seamróg (ˈʃamɣɾɣoːɡ), which is the diminutive of the Irish word for plant (seamair) and means simply "little plant" or "young plant". </P> <P> Shamrock usually refers to either the species Trifolium dubium (lesser clover, Irish: seamair bhuí) or Trifolium repens (white clover, Irish: seamair bhán). However, other three - leaved plants--such as Medicago lupulina, Trifolium pratense, and Oxalis acetosella--are sometimes called shamrocks . The shamrock was traditionally used for its medicinal properties (citation needed) and was a popular motif in Victorian times . </P> <P> There is still not a consensus over the precise botanical species of clover that is the "true" shamrock . John Gerard in his herbal of 1597 defined the shamrock as Trifolium pratense or Trifolium pratense flore albo, meaning Red or White Clover . He described the plant in English as "Three leaved grasse" or "Medow Trefoile", "which are called in Irish Shamrockes". The Irish botanist Caleb Threlkeld, writing in 1726 in his work entitled Synopsis Stirpium Hibernicarum or A Treatise on Native Irish Plants followed Gerard in identifying the shamrock as Trifolium pratense, calling it White Field Clover . </P>

What is another name for a three leaf clover