Lawless, Laighléis An English surname derived from the Middle English laweles meaning ‘an outlaw’. A family who came to Ireland at the time of the Cambro-Norman Invasion. A branch settled in Tirawley in Mayo. In 1890 the surname was principally found in Dublin and Galway, and the estimated number of bearers was 1,880. In the United States it is the 3,825th most numerous surname with an estimated 8,250 bearers.