William Leslie "Les" Thomas Williams (10 May 1922 – 27 January 2006) was a Welsh dual-code international rugby union, and professional rugby league footballer who played in the 1940s and 1950s. He played representative level rugby union (RU) for Wales, and at club level for Llanelli RFC and Cardiff RFC, as a wing, or centre, i.e. number 11 or 14, or 12 or 13, and representative level rugby league (RL) for Great Britain (non-Test matches), and Wales, and at club level for Hunslet, as a wing, or centre, i.e. number 2 or 5, or, 3 or 4.