The word 'strengthening' is built upon the Old English noun 'strength', which itself evolved from the Proto-Germanic adjective strangaz, meaning tight or strict, via the addition of a nominal suffix. The verb-forming suffix '-en', common in Germanic languages, was attached to create 'strengthen', meaning to make strong. Finally, the gerund suffix '-ing' nominalizes the action, resulting in a word that describes the process of becoming or causing to become more robust. The semantic journey reflects a concrete sense of physical power broadening to encompass abstract concepts of reinforcement and fortification in various contexts, from materials to institutions.

Structure: strength (strong) + en (verb suffix) + ing (gerund suffix) - strength: From Old English strengþu, strengð (power, force). A nominal suffix -þu was added to the adjective strang (strong). Its functional role is the core noun root. - en: A verb-forming suffix of Germanic origin, used to form verbs from adjectives or nouns (e.g., weaken, sharpen). Its role is to convert the noun 'strength' into the verb 'strengthen'. - ing: A suffix of Old English origin, forming verbal nouns (gerunds) or present participles. Its role here is to nominalize the verb 'strengthen', indicating the action or process.