internecine

in•ter•nec•ine (in-ter-nee'-seen, -nes'-een)  n

Definition:
1. mutually destructive; most often applied to warfare
2. characterized by struggle within a group, usually applied to an ethnic or familial relationship

Related: noxious, necro-

Examples:
• Unjust or inconsiderate retaliation removes the belligerents further and further from the mitigating rules of regular war, and by rapid steps leads them nearer to the internecine wars of savages. -1902
• When we speak of the struggle for existence, the popular view seems to construe this into the theory that the world is a mere cockpit, in which one race carries on an internecine struggle with the other. -1893

The Storyline
More the later, sad to say, lately was true: with the growing internecine conflict between the pair and self-destructive behavior evidencing itself presently.

Origin:
1663, from L. internecinus "very deadly, murderous, destructive," from internecare "kill or destroy," from inter (inter-) + necare "kill", from nec-, nex violent death. Considered in the OED as misinterpreted in Johnson's Dictionary [1755], which defined it as "endeavouring mutual destruction," on association of inter- with "mutual" when the prefix supposedly is used in this case as an intensive. From Johnson, wrongly or not, has come the main modern definition of "mutually destructive."

Sources: Wiktionary, Online Etymology, LanguageHat

Why This Word:
Ok, so you probably knew this word. But you probably didn't know -  I didn't - that we've been using it wrongly for centuries. Of course, it's too late to go back.

Now, I don't want to start any conflict - doesn't that just end up hurting everyone - but it looks like Samuel Johnson screwed up. Internecinus means "very deadly, murderous, destructive." The word first appeared in 1663 used as a rendering of Latin internecinum bellum, in Samuel Butler's Hudibras. "The prefix inter– was here used not in the usual sense 'between, mutual' but rather as an intensifier meaning 'all the way, to the death.' This piece of knowledge was unknown to Samuel Johnson, however, when he was working on his great dictionary in the 18th century. He included internecine in his dictionary but misunderstood the prefix and defined the word as 'endeavoring mutual destruction.' Johnson was not taken to task for this error. On the contrary, his dictionary was so popular and considered so authoritative that this error became widely adopted as correct usage."

On a side note, Wiktionary compounds the error in their etymology for internecine, assigning the incorrect meaning of between to the prefix inter- in this case.. "From Latin interneci-vus, deadly, alternatively, Latin inter (between) and necare (to slay)." I think most savvy internet users know that wiki- means use with caution. And I try to check with other sources before taking anything from Wiktionary. But here's another example of language change by error. Words mean what we say they do, genealogy notwithstanding. And the dictionary is the place we go to find what words are "supposed" to mean. With the internet largely supplanting print dictionaries, it's not hard to see errors propagating and become so common that become the consensus, and thereby correct.

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