Variant of Catherine, from Greek 'katharos' meaning pure or clean.
Cathryn is among the most elegant of the many variant spellings of one of history's most enduring names. Katherine — in its many forms Katarina, Catalina, Ekaterina, Caitlin — descends from the Greek Aikaterine, a name whose ultimate etymology has been debated for centuries. The most widely accepted derivation links it to the Greek katharos, meaning "pure" or "clean" — an etymology promoted by early Christian writers who associated the name with spiritual purity.
Others have suggested a connection to the goddess Hecate, though this is less linguistically secure. Whatever its exact roots, the name reached Western Europe partly through Saint Catherine of Alexandria, the fourth-century martyr whose brilliance and courage before Roman persecutors made her one of the most widely venerated saints of the medieval world. The long parade of famous Catherines and Katherines runs through European history like a royal procession: Catherine of Aragon and Catherine Howard among Henry VIII's wives; Catherine the Great, the German-born empress who ruled Russia with ferocious intelligence for thirty-four years; Catherine de' Medici, the Florentine queen who shaped French Renaissance politics; Catherine of Siena, declared a Doctor of the Church.
In literature, Catherine Earnshaw in Wuthering Heights gave the name a wild, passionate register quite different from the royal formality, and Catherine Morland in Northanger Abbey gave it comic charm. The Cathryn spelling — with its distinctive y where most forms place an i or e — carries a Welsh inflection, related to the Welsh form Catrin, and gives the name a quietly Celtic character. It was relatively common in mid-twentieth-century Wales and England and retains a soft differentiation from the more standard Katherine that many parents find appealing. It is a name of enormous historical substance worn in a slightly softer, more intimate form.