The shamrock is a symbol of Ireland. It is a three-leafed clover. It is sometimes of the variety Trifolium Repens (white clover, known in Irish as Seamair Bhán) but today usually Trifolium Dubium (lesser clover, Seamair Bhuí).
The diminutive version of the Irish word for 'clover' (seamair) is 'seamróg', which was anglicised as 'shamrock', representing a close approximation of the original Irish pronunciation. However, other three-leafed plants, such as black medic (Medicago Lupulina), red clover (Trifolium Pratense), and wood-sorrel (genus Oxalis) are sometimes designated as shamrocks. The shamrock was traditionally used for its medical properties and was a popular motif in Victorian times.
According to what the Oxford English Dictionary calls 'a late tradition' - first recorded in 1726, the plant was used by Saint Patrick to illustrate the doctrine of the Trinity. However, the posthumous timing of this legend, coming some 1,200 years after his death, and the lack of supporting evidence found in St. Patrick's writings have caused some to question its authenticity.
The shamrock has been registered as a trademark by the Government of Ireland. It is also informally used as an emblem for sports teams and state organisations within Ireland.
 | The four-leaf clover is often confused with the shamrock. While the four-leaf clover is a symbol of good luck, the three-leafed shamrock is mainly an Irish Christian symbol of the Holy Trinity and has a different significance. |
