Meaning A variant spelling of the name Cillian meaning 'war' or 'strife'. Origin of Killian Celtic , Irish Popular Middle Names James, Michael, Lee, Alexander, Grey, Charles, Francis, Jacob, John, Logan Pronunciation 🔊 Listen Killian KIHLY-ahN Similar Names Markel Kearne Lydell Edin Kaylub Callaghan Juozapas Ayan Clodius Cobi Year by Year Popularity of Killian