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

According to Cathy Owens, a political consultant and former Labour special adviser, the "internecine warfare" kick-started the party's drop in the polls in Wales.

From BBC

And Washington's threats have stoked polarization in a country still recovering from decades of internecine violence.

From Barron's

IMP’s rise could create internecine violence or, worse, deeper coordination between jihadist networks.

From The Wall Street Journal

The powerful pro-Israel lobby’s standing among Democrats has become a flash point amid broader internecine conflict in the Democratic Party over Israel’s unrelenting war in Gaza.

From Los Angeles Times