Wiktionary
extortionately
adv. In an extortionate manner; in a manner that greatly exceeds what is reasonable or moderate.
WordNet
extortionately
adv. to an exorbitant degree; "prices are exorbitantly high in the capital" [syn: exorbitantly, usuriously]
Usage examples of "extortionately".
But Calpurnia had to pay Euboule extortionately to keep the secret - and in the end Euboule or her daughter began to tell others.
This time I walked up the beach to an open-air bar and bought myself a glass of extortionately expensive iced orange juice.