When is a mistake not a mistake? In language at least, the answer to this
question is "When everyone adopts it," and on rare occasions, "When it's in the
dictionary."
The word internecine presents a case in point. Today, it usually has the meaning
"relating to internal struggle," but in its first recorded use in English, in
1663, it meant "fought to the death." How it got from one sense to another is an
interesting story in the history of English.
The Latin source of the word, spelled both internecinus and internecivus, meant
"fought to the death, murderous." It is a derivative of the verb necdre, "to
kill." 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 dicitonary was so popular and considered so authoritative that
this error became widely adopted as correct usage. The error was further
compounded when internecine acquired the sense "relating to internal struggle."
This story thus illustrates how dictionaries are often viewed as providing norms
and how the ultimate arbiter in language, even for the dictionary it self, is
popular usage.
