Killis is an uncommon given name of Greek origin, derived from the ancient city of Cyzicus located on the southern shore of the Propontis (modern-day Turkey). In ancient times, Cyzicus was renowned for its wealth and strategic importance, which likely contributed to the popularity of names associated with it. While not extensively used today, Killis remains a unique and historical name choice.
In the year 1905 alone, there were five individuals named Killis who were born annually.