the.com/firmness
The structural integrity of a thing, a handshake, or a refusal to budge.
means The quality of being solid, stable, and resistant to pressure — physically or in resolve.
from From Latin firmus, meaning strong or steadfast, the same root that braced up firm, affirm, and confirm — all promises that something will hold.
Mattress mythFirmest is not best for most backs.
Cheese scaleFirmness officially grades cheddar, gouda, and parmesan.
Linguistic cousinAffirm literally means to make firm.