Shamrocks are the young sprigs of clover or trefoil. The shamrock is a symbol of Ireland. According to a legend, Saint Patrick used it to illustrate the doctrine of the Holy Trinity. The name "shamrock" is derived from Irish '. This is the diminutive version of the Irish word for clover (') meaning simply ""little clover"" or ""young clover"". Sometimes other three-leafed plants are called shamrocks. The shamrock can be used for its medicinal properties. It was used as a motif in Victorian days. Around March 17 (Saint Patrick's Day) small pots of shamrocks are sold. Some people wear sprigs of shamrock in a buttonhole on the holiday.