arduously

The adverb 'arduously' is built upon the Latin adjective arduus, meaning "high, steep, or difficult," which itself is thought to derive from the Proto-Indo-European root h₃erdʰ-, meaning "to grow, high." The literal image is of a steep, towering climb requiring immense effort. This concrete sense of physical difficulty was retained as the word evolved, with the suffix -ous forming the adjective 'arduous' to describe tasks characterized by such demanding labor. Finally, the adverbial suffix -ly was appended, shifting the description to the manner in which an action—requiring persistent, strenuous, and exhausting effort—is performed.

Structure: ardu (steep, difficult) + ous (adjective suffix) + ly (adverb suffix) - ardu: From Latin arduus (high, steep, difficult). The root conveys the sense of a steep, challenging ascent. - ous: A suffix of Latin origin (-osus) used to form adjectives meaning "full of" or "characterized by" a quality. - ly: A suffix of Old English origin (-lice) used to form adverbs from adjectives, meaning "in a specified manner".