To affect as with something infused or instilled; imbue; impregnate; permeate: used especially of that which is bad or hurtful, but sometimes also of that which is good or indifferent.Specifically To taint with disease or the seeds of disease, either physical or moral: as, to infect a person with smallpox; literature infected with immorality.In law, to taint or contaminate with illegality, or expose to penalty, seizure, or forfeiture.Synonyms To poison, pollute, defile.Infected; tainted; affected unfavorably.Contaminated with illegality; having a flaw in the title.Marred; discolored; darkened.In philology, to affect the quality of a sound in a following or preceding syllable: used especially in reference to the influence of prominent vowels, and phonetic changes, in the Celtic language.