Kathryn is a 20th-century spelling of Katherine, from the Greek Aikaterine, a name of uncertain origin that has been linked since the early Christian era to katharos and read as "pure". Actress Katharine Hepburn and astronaut Kathryn Sullivan show the name's many spellings, and this one gives the nicknames Kate, Katie and Kat. Kathryn was a top 100 name in the United States from the 1930s to 2000, when it ranked number 89, and has since fallen to number 729 in 2025.