“Brand” doesn’t add anything to the meaning of “new,” so for formal writing it’s better to avoid it.
The other day, I heard something referred to as “brand new” and suddenly wondered where that expression comes from. The wonderful Word Detective explains that “brand” comes from Old English, in which it meant “fire” or “a torch.” Something that was brand-new would have been something just out of the fires of creation, like a forged sword or a pottery bowl. Shakespeare actually used “fire-new” to mean the same thing in several plays.
“Bran-new” is a common variation on “brand-new,” although it’s usually considered an error. If memory serves, it was used more commonly some years ago but it still appears fairly often online.
It appears that the advice that Dorothy got lo those many years ago was entirely backwards. Brand-new is the historically earlier form, and bran-new arose as a kind of reinterpretation. But that reinterpretation has proved remarkably sturdy over the years, to the extent that some speakers of English (as in Dorothy’s neck of the woods) take it to be the primary form, with brand-new as a mispronunciation/misspelling that ought to be “corrected.”
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