firm 1 
(fûrm)
(fûrm)adj. firm·er, firm·est
1. Resistant to externally applied pressure.
2. Marked by or indicating the tone and resiliency of healthy tissue: firm muscles.
3. Securely fixed in place: Despite being hit by the car, the post was still firm.
4. Indicating or possessed of determination or resolution: a firm voice.
5. Constant; steadfast: a firm ally.
6.
a. Not subject to change; fixed and definite: a firm bargain; a firm offer.
b. Unfluctuating; steady: Stock prices are still firm.
7. Strong and sure: a firm grasp.
tr. & intr.v. firmed, firm·ing, firms
To make or become firm. Often used with up.
adv. firmer, firmest
Without wavering; resolutely: stand firm.
[Middle English ferm, from Old French, from Latin firmus; see dher- in the Appendix of Indo-European roots.]
firmly adv.
firmness n.