extortionate

As an adverb inordinately

is in an inordinate manner.

As an adjective extortionate is

of, related to or typifying extortion.

As adjectives the difference between extortive and extortionate

is that extortive is involving, constituting or accomplished by extortion(attention) while extortionate is of, related to or typifying extortion.

As adjectives the difference between extortionate and prohibitive

is that extortionate is of, related to or typifying extortion while prohibitive is tending to prohibit, preclude, or disallow.

As a noun prohibitive is

negative imperative.

As adjectives the difference between extravagant and extortionate

is that extravagant is exceeding the bounds of something; roving; hence, foreign while extortionate is of, related to or typifying extortion.

As adjectives the difference between extortionate and upmarket

is that extortionate is of, related to or typifying extortion while upmarket is designed for customers with a high income.

As an adverb upmarket is

towards the more expensive end of the market.

As adjectives the difference between extortionate and expensive

is that extortionate is of, related to or typifying extortion while expensive is having a high price or cost.

As a noun taxonomy

is the science or the technique used to make a classification.

As an adjective extortionate is

of, related to or typifying extortion.

As adjectives the difference between extortionate and unaffordable

is that extortionate is of, related to or typifying extortion while unaffordable is too expensive to be afforded.

As adjectives the difference between extortionate and overpriced

is that extortionate is of, related to or typifying extortion while overpriced is priced higher than what it is really worth.

As a verb overpriced is

(overprice).