Yes, premium is a Scrabble word!

Adjective

1. Having or reflecting superior quality or value

Noun

1. Payment for insurance

2. The amount that something in scarce supply is valued above its nominal value

3. A fee charged for exchanging currencies

4. A prize, bonus, or award given as an inducement to purchase products, enter competitions initiated by business interests, etc.

5. Payment or reward (especially from a government) for acts such as catching criminals or killing predatory animals or enlisting in the military