infect
Formsinfects, infecting, infected
Formsinfects, infecting, infected
- 1To bring a body or body part into contact with a pathogen so the pathogen begins acting on it; or, of a pathogen, to enter a body and start to act.
The contaminated needle infected several patients before anyone noticed.
Health officials feared the new strain could infect millions within weeks.
Note
Behind the medical verb is a Latin image of staining: inficere meant "dye, taint", and its participle infectus reached English through Middle French. Either side can be the subject. A carrier or a needle infects a patient, or a virus infects humans. In the passive the agent follows with by, as in infected by the virus.
- 2To contaminate an object or substance with a disease-causing pathogen.
Improperly stored meat had infected the entire batch.
Researchers deliberately infect the samples to test the new disinfectant.
Similarcontaminate, taint, pollute
Oppositedisinfect, sterilize, decontaminate
- 3To fill someone with your own enthusiasm, or to spread a feeling to others so that it catches on.
His optimism infected everyone in the office within days.
Festival crowds can infect newcomers with sudden, giddy energy.
Similarinspire, fill, imbue, affect
Note
Feelings spread here the way germs do in the medical sense. The feeling itself can be the subject: Letitia Elizabeth Landon, in Francesca Carrara (1834), writes of an embarrassment "which seemed to infect them all". A person can be the subject too, infecting others with enthusiasm. The verb suits moods that pass from one person to many, such as passion, optimism or unease.
Less common meanings
- 4Affected by or tainted with disease; infected.
And in the imitation of these twain, / Who, as Ulysses says, opinion crowns / With an imperial voice, many are infect.
c. 1602, William Shakespeare, “The Tragedie of Troylus and Cressida”Note
Shakespeare's word, not ours. In Troilus and Cressida (c. 1602) "many are infect", where a modern writer would say infected. The form is the Latin participle infectus, borrowed through Middle French, so it never needed an -ed. It takes no comparison. In present-day writing it reads only as a deliberate archaism, and infected is the safe choice.
- 5Designating a verb form that represents an action as ongoing or not yet completed.
Latin grammarians grouped the present, imperfect, and future under the infect system.
An infect stem marks the action as still unfolding rather than finished.
Similarimperfective
Oppositeperfect, perfective
Note
A separate word that happens to share the spelling. It comes from Latin in- "not" plus factus "done", so it literally means "not done" and has nothing to do with disease. Grammarians use it, rarely, for tenses that present an action as still unfinished. In Latin these are the present, imperfect and future, set against the completed forms. Outside that technical setting readers will hear the medical verb, so explain the term when you use it.
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Practice
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Origins
From Middle French 'infect', from Latin 'infectus', the perfect passive participle of 'inficio' meaning 'to dye or taint'.
Borrowed from Latin 'infectus', which combines 'in-' ('not') with 'factus', the perfect passive participle of 'facio' ('to do, make').