Yes, hotter is a Scrabble word!

Adjective

1. Used of physical heat; having a high or higher than desirable temperature or giving off heat or feeling or causing a sensation of heat or burning

2. Characterized by violent and forceful activity or movement; very intense

3. Extended meanings; especially of psychological heat; marked by intensity or vehemence especially of passion or enthusiasm

4. (color) bold and intense

5. Sexually excited or exciting

6. Recently stolen or smuggled

7. Very fast; capable of quick response and great speed

8. Wanted by the police

9. Producing a burning sensation on the taste nerves

10. Performed or performing with unusually great skill and daring and energy

11. Very popular or successful

12. Very unpleasant or even dangerous

13. Newest or most recent

14. Having or bringing unusually good luck

15. Very good; often used in the negative

16. Newly made

17. Having or showing great eagerness or enthusiasm

18. Of a seeker; very near to the object sought

19. Having or dealing with dangerously high levels of radioactivity

20. Charged or energized with electricity

21. Marked by excited activity