Triinu

Triinu is an Estonian feminine name that developed as a pet form of Katariina, the Estonian form of Katherine, itself derived from the Greek name Aikaterine, whose meaning remains debated but is often associated with the Greek word katharos, meaning pure. The name passed into Estonian folk usage as an affectionate diminutive and eventually became an independent given name in its own right. Related forms include Katariina, Kaarina, and Karin.