Lexicon (Gesenius)

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Gesenius wrote a Lexicon which was a foundational work in the history of Hebrew dictionary-making. It was in German, which was the dominant language for a time in modern Hebrew scholarship. It came out in 1829, and remains online to the present. For English-readers, it is likely to be found in the form of the translation by Tregelles.

Now, Gesenius had a modern outlook on the Bible, and so naturally his views appeared to be heresy to a more traditionally-minded person like Tregelles. And so in Tregelles' translation of Gesenius, Tregelles continually adds little anti-modernist notes in brackets throughout, creating the odd spectacle of a Hebrew lexicon arguing with itself.

The Lexicon of Gesenius was supplanted by Brown-Driver-Briggs, which came out in 1906. Falling ahead of the 1923 deadline for materials copyrighted in the United States, it is also available online. Trust only the online facsimile copies. There are abridgments or modifications circulating in HTML form passing themselves off as BDB when they are far from the genuine article.

BDB was followed by HALOT, the Hebrew and Aramaic Lexicon of the Old Testament, which appeared from 1994 to 2000. HALOT's major rival is the Dictionary of Classical Hebrew (DCH), which takes a somewhat different approach to how Hebrew terms have meaning, and which was published from 1993 to 2011.

Gesenius, BDB, and HALOT, we could say, fall on the side of leaning heavily on etymology as a way of understanding the meanings of Hebrew terms, while on the other hand DCH relies more heavily on usage within Hebrew itself. Neither approach can yield certainty for many of the rarest terms in Hebrew. The corpus is simply to limited.

So while all these reference works are worthwhile, none are final arbiters on the meaning of Hebrew and Aramaic terms within the Bible.