William Andrew Gianopoulos, 74, of Ashland, passed away unexpectedly at his home on Monday, January 6, 2025. Born in Boston, he was the son of the late Irene (Kafalas) and George Gianopoulos. He was the husband of 27 years to the late Barbara (Burak) Chicklis. 

William worked as a Senior Principal Cyber Engineer at Raytheon, where he was respected for his expertise, dedication, and contributions to the field of cybersecurity. He also enjoyed working on computers at his home. William was also an avid music lover. He had a special place in his heart for live music and enjoyed attending concerts, with a particular fondness for Bruce Springsteen.  

William is survived by his step-daughter, Karen O’Brien and her husband Michael of Holliston, his siblings, Peter Gianopoulos and his wife Carol of Andover, George Gianopoulos of Belmont, and Jean Jesensky and her husband John of Florida. He also leaves behind his grandchildren, Mannis O’Brien, his wife Mary, and Kayla, and Liam O’Brien, as well as five nieces and nephews. He was excited about his first great-granddaughter due in April. He is predeceased by his step-son, Paul Chicklis. 

Private family arrangements are being held and are under the care of the Chesmore Funeral Home of Holliston.