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Book of Mormon/Language/Names/Coriantumr
The name "Coriantumr" in the Book of Mormon
The Church of Jesus Christ of Latter-day Saints responds to these questions
Elder Marcus B. Nash, "‘Out of Weakness He Shall Be Made Strong’," 70th Annual Joseph Smith Memorial Devotional (history.lds.org), (3 June 2013)
Joseph, a poor speller, corrected Oliver’s first spelling of the name “Coriantumr.” The first time it was dictated, we find in the original transcript that it was spelled by the scribe (who was Oliver Cowdery at that time) as “Coriantummer.” This was reasonable, since there are no English words that end in “mr.” However, Joseph—who was a weak enough speller to accept the spelling the Lord gave to him (and not tell the Lord that there are no words that end in “mr”), corrected the spelling in the same line (that is, during the translation), so that it ends as it now appears in the Book of Mormon. We now know that while this is poor spelling in English, it is perfectly good Egyptian spelling and fits well into the Old World setting. Most readers of the Book of Mormon—then and now—do not know this, nor would Joseph have known this but for revelation....(Click here for full article)
On “Coriantumr” and the spelling of proper names, see Royal Skousen, “Translating the Book of Mormon: Evidence from the Original Manuscript,” in Book of Mormon Authorship Revisited: The Evidence for Ancient Origins, ed. Noel B. Reynolds (Provo, Utah: Foundation for Ancient Research and Mormon Studies, 1997), 61-93. Using evidence from the original manuscript, Skousen shows that the first time proper names appeared in the text, they were spelled correctly; in subsequent appearances the names may or may not be spelled correctly, suggesting that the Joseph Smith spelled out each name the first time but relied on the scribe’s memory thereafter.
The Neal A. Maxwell Institute provides additional information on this subject
Royal Skousen,"Translating the Book of Mormon: Evidence from the Original Manuscript", Book of Mormon Authorship Revisited, (1997)
In this case, no matter how slowly or carefully Joseph Smith might have repronounced Coriantumr, it would have been impossible for him to have indicated that there was no vowel between the m and r at the end of the name except by actually spelling out the separate letters m and r. Nor could Oliver Cowdery have guessed this spelling since no word (or name) in English ends in mr. In fact, Oliver ends the correct spelling Coriantumr with a large flourish on the final r, which Oliver produces nowhere else in either the original or the printer's manuscript. This addition probably reveals Oliver Cowdery's frustration at having to guess at such a weird spelling.(Click here for full article)