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Showing results for prophylaxis. Search instead for biophylaxis.
Synonyms

prophylaxis

American  
[proh-fuh-lak-sis, prof-uh-] / ˌproʊ fəˈlæk sɪs, ˌprɒf ə- /

noun

  1. Medicine/Medical.

    1. the preventing of disease.

    2. the prevention of a specific disease, as by studying the biological behavior, transmission, etc., of its causative agent and applying a series of measures against it.

  2. prophylactic treatment, as the cleaning of the teeth by a dentist or dental hygienist.


prophylaxis British  
/ ˌprɒfɪˈlæksɪs /

noun

  1. the prevention of disease or control of its possible spread

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of prophylaxis

1835–45; < New Latin < Greek pro- pro- 2 + phýlaxis a watching, guarding, equivalent to phylak- (base of phylássein to guard) + -sis -sis

Explanation

Prophylaxis refers to all the things people do to prevent disease. Prophylaxis is part of medicine. If you've ever heard of someone using prophylactics to prevent a disease — often a sexually transmitted disease — then you have a clue to the meaning of prophylaxis, which refers to the prevention of disease. Anything you do to stay healthy and keep illness at bay would be categorized as prophylaxis. Antibiotic prophylaxis refers to giving patients antibiotics to prevent a bacterial infection, instead of curing an infection that already exists.

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Vocabulary lists containing prophylaxis

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Pre-exposure prophylaxis, or PrEP, has been used for over a decade to prevent HIV, but its reliance on a daily pill has limited its impact on global infections.

From Barron's • Dec. 1, 2025

I started off pretty skeptical about echinacea, but actually, I’m an author on studies showing that echinacea reduces antibiotic usage by about 70 percent in children if they use it as a prophylaxis.

From Slate • Oct. 8, 2025

It is hoped it will replace the current form of HIV preventative drug, know as PrEP, or pre-exposure prophylaxis, which is taken orally and also costs $40 per person each year.

From BBC • Sep. 24, 2025

The CDC supports providing such post-exposure prophylaxis to all asymptomatic household contacts within 21 days of when a whooping cough patient starts coughing.

From Los Angeles Times • Nov. 22, 2024

Her secret prophylaxis was a white bag, filled and saturated with camphor, which she kept hidden in her bosom.

From "Cheaper by the Dozen" by Frank B. Gilbreth Jr. and Ernestine Gilbreth Carey