Władysław I the Elbow-high of Kujawy, however, as he had two older half-brothers from Casimir’s second marriage to Constance of Wrocław: Leszek II the Black ("Leszek Czarny") and Ziemomysł. He was named after his uncle, his mother's brother Władysław, Duke of Opole. Already in contemporary sources he was nicknamed ""Łokietek"", a diminutive of the word "łokieć". It translates as "elbow" or "ell" – a medieval unit of measure similar to a cubit, as in "elbow-high". The origin of this nickname, as resulting from Władysław’s short stature, was explained only in the 15th century by historian Jan Dlugosz. In 1267, when Władysław the Elbow-high was
Ancient Greek units of measurement measures of length were named after parts of the body, such as the ("daktylos", plural: "daktyloi") or finger (having the size of a thumb), and the ("pous", plural: "podes") or foot (having the size of a shoe). The values of the units varied according to location and epoch (e.g., in Aegina a "pous" was approximately , whereas in Athens (Attica) it was about ), but the relative proportions were generally the same. The ordinary units used for land measurement were: Greeks measured volume according to either dry or liquid capacity, suited respectively to measuring grain and wine. A common unit