An extremely rare historical term, possibly meaning to confuse or distort (a variant or corruption of 'garble'), though documentation is scarce.
Possibly from prefix 'en-' plus 'garble' (from Arabic 'gharbala', to sift or select), but this word is so obscure that its true etymology is uncertain. It may be a ghost word—an error that got perpetuated in dictionaries.
Some words in historical dictionaries are 'ghost words'—errors that got copied so many times nobody's sure if they were ever real! 'Engarble' might be one of these phantom words that linguists still argue about.
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