Yes, say is a Scrabble word!

Verb

1. Express in words

2. Report or maintain

3. Express a supposition

4. Have or contain a certain wording or form

5. Give instructions to or direct somebody to do something with authority

6. Speak, pronounce, or utter in a certain way

7. Communicate or express nonverbally

8. Utter aloud

9. State as one's opinion or judgement; declare

10. Recite or repeat a fixed text

11. Indicate

Noun

1. The chance to speak