Dennis O'Neil

life story

Dennis J. O'Neil III

Forever in our hearts!

On March 28, 2026, Dennis J. O’Neil III entered eternal rest while under hospital care. His nephew and niece George and Susan Underco were by his side to offer love and comfort.

Dennis has progressed on to his “Heavenly Life”, where his soul is pure and free. He was welcomed with open, loving arms and reunited with his dearest family members that preceded him in death; his devoted wife of 33 years, Lauri O'Neil, parents Dennis J. O'Neil II and Dorothy M. O'Neil, his elder sister Kathleen "Peggy" O'Neil and beloved niece Lisa (Underco) Schinness.

A dear brother, uncle, great uncle and friend; many hearts hurt from your loss...

Dennis is survived by his loving sister(s) Patricia O'Neil and Denise Gasper. His niece, Kelly Manning, nephew George Underco and his wife Susan, great nephews Jim and Dan Underco and great niece Samantha Schinness, brother-in-law Roger Gasper and many extended family members. Last but not least, Dennis is survived by his best friend of 60+ years, Gary Dahl and his wife Judy. Their friendship spanned generations; each considered the other to be a "true brother"..

Dennis was born in Warrensville Heights and resided in the Cleveland Metro area for the majority of his life.

He graduated from Maple Heights High School, Alumni-Class of 1970. Dennis was an accomplished and respected member of the Maple Heights High School wrestling team; the school and contributing team members acquired many notable achievements within their division during the years of 1966 through 1969.

Dennis attended ITT Technical Institute where he excelled at his studies. Through his dedication and knowledge acquired, the path was paved for employment opportunities; ultimately securing a position with Avtron Power Solutions. During the course of his employment; he was promoted to an instructor position that progressed into a project management role where he traveled internationally, working on large scale technology endeavors and educating many colleagues along the way.

He embodied the true Irish spirit; having a good heart and protecting the one’s he loved. He was a “one of a kind” man who enjoyed life to the fullest and he lived it with zest!

Dennis had a wit about him, along with a good sense of humor. He took after his father in this respect, having a jovial nature. Both liked entertaining other's through laughter; especially children...

All throughout his life, he was a very talented artist; drawing freehand style with passion and creativity. In the prime of his life, he studied and practiced martial arts and lifted weights to keep fit.

Dennis was a long time, die-hard Browns fan! The games between Cleveland and Pittsburgh were always an intense event yet a favorite of his to watch on TV with family and friends. His support for the hometown team never waivered...

He enjoyed reading and learning, deep thought-provoking conversations, playing chess and cooking.

His favorite vocal artist was Paul Rodgers and he additionally appreciated the singing talents of Chris Cornell, The Black Crowes, listening to the soulful sounds of "The Blues" and many more...

He enjoyed watching many genres of movies; was a fan of the actor Jack Nicholson, admired the acting diversity of Sam Rockwell and liked binge watching the TV series, Better Call Saul.

In the 70's, Saturday Night Live and "The Coneheads" skit, were a favorite (played by Dan Aykroyd and Jane Curtain). Liking the character(s) so much, he dressed up as such one Halloween and pulled it off amazingly well...

Dennis had many pets throughout his life whom he enjoyed spending time with, whether it be going to the park, playing frisbee, walks/hiking and while living in Florida, swimming in the ocean...

This isn't goodbye, it's until we meet again...

memorial service

No Public Service

Please feel free to use the guestbook to share your memories, thoughts or even a funny story about Dennis with the O'Neil family; as it would be kindly appreciated. Thank You!