the compound 'stiff-backed' is a transparent formation from two english elements. the adjective 'stiff', with its ancient germanic roots conveying inflexibility, combines with 'backed', a participial adjective from 'back', referring to the rear part of the torso or an object. the literal sense describes something, like a person's posture or a book's spine, that is rigidly straight. figuratively, it evolved to characterize a person who is formal, haughty, or unyielding in demeanor, metaphorically extending the physical rigidity to an attitude.

Structure: stiff (rigid) + backed (having a back) 'stiff' originates from old english stīf, meaning rigid, firm. 'backed' is derived from the noun 'back' (old english bæc) combined with the suffix '-ed', indicating possessing a specified feature.