The word 'unyielding' is a straightforward English compound built from native Germanic elements. The core verb 'yield,' from Old English gieldan, originally meant "to pay" but evolved to signify "to give way, concede, or surrender" under pressure or force. The negative prefix 'un-,' one of the most common in English, directly reverses this action. The adjectival suffix '-ing' transforms the verbal idea into a descriptive state of being. Thus, the literal construction "not-giving-way" perfectly captures the modern abstract meanings of steadfastness, rigidity, and resoluteness.

Structure: un (not) + yield (give way) + ing (adjective suffix) - un: A prefix of Germanic origin (Old English un-), meaning "not." It functions as a negative particle. - yield: A verb of Germanic origin (Old English gieldan, meaning "to pay, give"). In this compound, it carries the sense of "giving way, surrendering." - ing: A suffix of Germanic origin (Old English -ende, -ing), used to form present participles and adjectives from verbs, indicating a quality or state.