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


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

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 Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for prophylaxis

British Dictionary definitions for prophylaxis

/ (ˌprɒfɪˈlæksɪs) /


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

Medicine definitions for prophylaxis

[ prō′fə-lăksĭs, prŏf′ə- ]

n. pl. pro•phy•lax•es (-lăksēz′)

Prevention of or protective treatment for disease.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.