infective

adjective

in·​fec·​tive in-ˈfek-tiv How to pronounce infective (audio)
a
: producing or capable of producing or transmitting infection
infective oocysts are ingested with contaminated feed or water.Douglas N. Stern
Affected cats not yet showing signs of illness may shed the virus and be infective to other cats …Cat Fancy
b
: caused by or resulting from an infection with one or more pathogenic agents
infective bacterial endocarditis
c
: affecting others : spreading easily to others
Different teachers will demonstrate different skills and strengths. Some will have … an infective enthusiasm for their own subject.Jonathan Glazzard et al.

Examples of infective in a Sentence

Recent Examples on the Web
These examples are automatically compiled from online sources to illustrate current usage. Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.
On July 30, Ray updated her fans again, revealing her diagnosis of infective endocarditis, a severe heart infection. Jessica Lynch, Billboard, 31 July 2024 Hospitalizations for strokes related to opioid use and infective endocarditis, a life-threatening infection of the heart’s lining and valves, increased in people under 45 from 2006 through 2015, coinciding with the opioid epidemic’s onset, the authors added. Elizabeth Cooney, STAT, 23 May 2024 Handling of the raw fish can also deliver the infective larva to the intestinal system. Rebecca Kreston, Discover Magazine, 27 Sep. 2011 People typically get malaria by being bitten by an infective female Anopheles mosquito. Sara Moniuszko, CBS News, 5 Oct. 2023 See all Example Sentences for infective 

Word History

Etymology

Middle English infectif "causing disease, infectious," borrowed from Medieval Latin infectīvus "infectious, poisonous" (Latin, "used for dyeing"), from Latin infectus, past participle of inficere "to dye, discolor, taint, contaminate with disease" + -īvus -ive — more at infect

First Known Use

14th century, in the meaning defined above

Time Traveler
The first known use of infective was in the 14th century

Dictionary Entries Near infective

Cite this Entry

“Infective.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/infective. Accessed 11 Nov. 2024.

Kids Definition

infective

adjective
in·​fec·​tive in-ˈfek-tiv How to pronounce infective (audio)
: producing or able to produce infection
infectivity noun

Medical Definition

infective

adjective
in·​fec·​tive in-ˈfek-tiv How to pronounce infective (audio)
a
: producing or capable of producing or transmitting infection
infective oocysts are ingested with contaminated feed or water.Douglas N. Stern
… a strain of bacteria which forms spores that can remain infective for as long as fifty years.Sue Hubbell
Affected cats not yet showing signs of illness may shed the virus and be infective to other cats …Cat Fancy
b
: caused by or resulting from an infection with one or more pathogenic agents
infective bacterial endocarditis

More from Merriam-Webster on infective

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!