The word 'uninfected' is a modern English formation built upon the verb 'infect'. The core verb 'infect' entered English via Old French from Latin inficere, which literally meant "to put in, to dip, to stain," combining in- (into) and facere (to make). This evolved from a sense of physical staining to the metaphorical staining of health. The Germanic negative prefix 'un-' was then attached to create the opposite meaning. Finally, the past participle suffix '-ed' functions adjectivally to describe the state of not having undergone the process of infection. Thus, the word's logic transparently follows a path from "not made into (a stained/tainted state)."

Structure: un (not) + infect (contaminate) + ed (adjective suffix) - un: A prefix of Germanic origin (Old English) meaning "not," used to form negatives. - infect: From Latin inficere (to stain, dye, taint), from in- (in, into) + facere (to make, do). In English, it means to contaminate with a disease-causing agent. - ed: A suffix of Germanic origin (Old English) used to form adjectives from verbs or nouns, indicating a state or condition.