The phrase "enormous disservice" means doing something that is very harmful or unfair to someone or something. It describes a situation where someone is being treated badly or not receiving what they deserve. Full definition
Of Schneiderman speaking at the Sunday event, Hein said: «I believe he did an enormous disservice to all the wonderful people in attendance.» (dailyfreeman.com)
But more prevalent are cases like mine: students for whom the rigors of college life were a rude awakening, to whom their schools did an enormous disservice by expecting less than they were capable of. (educationnext.org)
The rollback and other policies that ignore climate change «do an enormous disservice to the public by denying or minimizing the urgency of human - caused climate change,» said Pushker Kharecha, a climate scientist at The Earth Institute at Columbia University. (livescience.com)