Comparative form of holy: more holy; more sacred.(adjective)
Comparative form of holey: more holey; more full of holes.(adjective)
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Use "holier" in a sentence
"Mr. Anderson was also bugged by what he describes as the holier-than-thou attitude typified by Critical Mass, a monthly gathering of bikers who coast through the city, snarling traffic for hours."
"In recent years, social psychologists have begun to study what they call the holier-than-thou effect."
"Do you think these irrelevant standards are applied any where other than in "holier than thou" America?"