The definition of infect is to contaminate someone or something with a disease or with some other negative element.(verb)
See infect in Webster's New World College Dictionary
Origin: ME infecten < MFr infecter < L infectus, pp. of inficere, to put or dip into, tinge, stain < in-, in + facere, to do
See infect in American Heritage Dictionary 4
transitive verb in·fect·ed, in·fect·ing, in·fects
Origin: Middle English infecten, to afflict with disease
Origin: , from Latin īnficere, īnfect-, to stain, infect (in-, in; see in-2 + facere, to do; see dhē- in Indo-European roots).
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