premium

As an adjective upscale

is (us) marked by wealth or quality; high-class.

As a verb upscale

is to increase in size, to scale up.

As a noun premium is

bonus (extra amount of money given as a premium).

As an adjective optimal

is the best, most favourable or desirable, especially under some restriction.

As a noun premium is

bonus (extra amount of money given as a premium).

As a noun premium

is bonus (extra amount of money given as a premium).

As an adjective costly is

of high cost; expensive.

As a noun premium

is bonus (extra amount of money given as a premium).

As an adjective undefined is

lacking a definition or value.

As nouns the difference between premium and membership

is that premium is bonus (extra amount of money given as a premium) while membership is the state of being a member of a group or organization.

As nouns the difference between mass and premium

is that mass is march while premium is bonus (extra amount of money given as a premium).

As nouns the difference between powerhouse and premium

is that powerhouse is any source of power, energy or strength while premium is bonus (extra amount of money given as a premium).

As a noun premium

is bonus (extra amount of money given as a premium).

As an adjective exorbitant is

exceeding proper limits; extravagant; excessive or unduly high.

As adjectives the difference between premium and taxing

is that premium is superior in quality; higher in price or value while taxing is with respect to an experience: exhausting; draining.

As nouns the difference between premium and taxing

is that premium is a prize or award while taxing is the act of imposing a tax.

As a verb taxing is

present participle of lang=en.

As nouns the difference between amplification and premium

is that amplification is the act, or result of amplifying, enlarging, extending or adding while premium is bonus (extra amount of money given as a premium).