Yes, special is a Scrabble word!

Adjective

1. Unique or specific to a person or thing or category

2. For a special service or occasion

3. Surpassing what is common or usual or expected

4. Adapted to or reserved for a particular purpose

5. Having a specific function or scope

6. First and most important

7. Added to a regular schedule

Noun

1. A special offering (usually temporary and at a reduced price) that is featured in advertising

2. A dish or meal given prominence in e.g. a restaurant

3. A television production that features a particular person or work or topic