prophylactic

UK: /ˌprɒfɪˈlæktɪk/

US: /ˌproʊfəˈlæktɪk, ˌprɑfə-/

US: (prō′fə lak′tik, prof′ə-)

WordReference Random House Learner's Dictionary of American English © 2025

pro•phy•lac•tic /ˌproʊfəˈlæktɪk, ˌprɑfə-/   adj. 

1. Medicine preventing or protecting from disease or infection.

n. [countable]

2. Medicine a medicine or measure that prevents or protects from disease or infection.
3. a device used to prevent conception or venereal infection, esp. a condom.

WordReference Random House Unabridged Dictionary of American English © 2025

pro•phy•lac•tic  (prō′fə lak′tik, prof′ə-), adj. 

1. Drugs defending or protecting from disease or infection, as a drug.
2. preventive or protective.

n. 

3. Medicine a prophylactic medicine or measure.
4. a preventive.
5. a device, usually a rubber sheath, used to prevent conception or venereal infection;
   condom.

• Greek prophylaktikós of guarding, equivalent. to prophylak- (base of prophylássein to guard beforehand) + -tikos -tic. See prophylaxis
• 1565–75

pro′phy•lac′ti•cal•ly, adv. 

Collins Concise English Dictionary © HarperCollins Publishers::

prophylactic / ˌprɒfɪˈlæktɪk/ adjective

1. protecting from or preventing disease
2. protective or preventive

noun

1. a prophylactic drug or device, esp a condom

Etymology: 16th Century: via French from Greek prophulaktikos, from prophulassein to guard by taking advance measures, from pro-² + phulax a guard