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.

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prophylaxis British  

/ ˌprɒfɪˈlæksɪs /

noun

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

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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

Example Sentences

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

Officials call the treatment doxy PEP, short for doxycycline postexposure prophylaxis.

From Seattle Times • Jun. 4, 2024

She had no prophylaxis, unfortunately, for Death by Drowning.

From "The God of Small Things" by Arundhati Roy