Yes, firm is a Scrabble word!
...and is worth 9 points in Scrabble, and 10 points in Words with Friends
firm
Adverb
1. With resolute determination
Verb
1. Become taut or tauter
2. Make taut or tauter
Adjective
1. Marked by firm determination or resolution; not shakable
2. Not soft or yielding to pressure
3. Strong and sure
4. Not subject to revision or change
5. (of especially a person's physical features) not shaking or trembling
6. Not liable to fluctuate or especially to fall
7. Securely established
8. Possessing the tone and resiliency of healthy tissue
9. Securely fixed in place
10. Unwavering in devotion to friend or vow or cause
Noun
1. The members of a business organization that owns or operates one or more establishments
What Scrabble words can I make with the letters in firm?
3 Letter Words
2 Letter Words