Other Words for Backbone
Backbone as a Noun has these synonyms:
Example: Sheila has been the backbone of the society, but she has now moved away.
resoluteness, sturdiness, firmness, determination, strength (of character), mettle, purposefulness, resolution, courage, fortitude, resolve, will, will-power, strength, stability, stamina, staying power, grit
Example: Has she the backbone to run the company alone.
spine, spinal column
Example: He's much better since the surgery on his backbone.