internecine

American  

[in-ter-nee-seen, -sahyn, -nes-een, -nes-ahyn] / ˌɪn tərˈni sin, -saɪn, -ˈnɛs in, -ˈnɛs aɪn /

Also internecive

adjective

1. of or relating to conflict or struggle within a group.

   an internecine feud among proxy holders.

2. mutually destructive.

3. characterized by great slaughter; deadly.

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internecine British  

/ ˌɪntəˈniːsaɪn /

adjective

1. mutually destructive or ruinous; maiming both or all sides

   internecine war

2. of or relating to slaughter or carnage; bloody

3. of or involving conflict within a group or organization

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Etymology

Origin of internecine

1655–65; < Latin internecīnus, internecīvus murderous, equivalent to internec ( āre ) to kill out, exterminate ( inter- inter- + necāre to kill) + -īnus -ine ¹, -īvus -ive

Example Sentences

Afghanistan’s internecine bloodshed has an epiphanic effect on the author: “When death stalks every door,” she writes in a burst of originality, “the only antidote is to live.”

From The Wall Street Journal • Nov. 20, 2025

The rebel factions have a history of division and internecine fighting.

From BBC • Dec. 7, 2024

Every year in cities across the country, this sort of internecine conflict undoubtedly happens.

From Los Angeles Times • Oct. 24, 2024

Because both sides are viruses, the results of this internecine war necessarily include something of interest to people: antivirals.

From Salon • Nov. 9, 2023

Along the way, there is internecine strife between the gods and some flying Hell’s Angels, the magnificently apocalyptic Valkyries.

From "The Story of Music" by Howard Goodall