Yes, smart is a Scrabble word!

Verb

1. Be the source of pain

Adjective

1. Showing mental alertness and calculation and resourcefulness

2. Elegant and stylish

3. Characterized by quickness and ease in learning

4. Improperly forward or bold

5. Painfully severe

6. Quick and brisk

7. Capable of independent and apparently intelligent action

Noun

1. A kind of pain such as that caused by a wound or a burn or a sore