Gesenius' Hebrew grammar: 17th ed., with numerous corrections and additions, by dr. E. Rödiger. Tr. by T. J. Conant ... With grammatical exercises and a chrestomathy, by the translator.

PART SECOND.
01; FORMS AND INFLEXIONS, OR OF THE PARTS OF
SPEECH.
SECT. 30.
OF TH1t STEM-WORDS AND ROOTS (BILITERALS, TRILITERALS, QUADRILITERALS).
1. THut stem-words of the Hebrew and of the other Shemitish languages have this peculiarity, that by far the most of
them consist of three consonants, on which the meaning essentially depends, while its various modifications are expressed by
changes in the vowels, e. g. 01_ he was red, t:& red, 13, man
(prop. red one) Such a stem-word may be indifferently either
a verb or a noun, and usually the language exhibits both together, as Bi' he has reigned, J:b. king. Yet it is customary
and of practical utility for the beginner, to consider the third
person singular of the Preterite, i. e. one of the most simple
forms of the verb, as the stem-word, and the other forms of both
the verb and the noun, together with most of the particles, as
derived from it, e. g.?12 he was righteous, p;2 righteousness,
pet righteous, &c. Sometimes the language, as handed down
to us, exhibits only the verbal stem without a corresponding form
for the noun, as b5P to stone, Pr? to bray; and occasionally the
noun is found without the corresponding verb, e. g. ~a south
Pt' nine. Yet it must be supposed that the language, as
spoken, often had the forms now wanting [most of them being
actually found in the cognate dialects].
Rem. 1. The Jewish grammarians call the stem-word, i.e. the third
person singular of the preterite, the root, 5t9, for which the Latin term
radix is often used; and hence the three consonants of the stem are called
radical letters, in contradistinction from the servile letters [namely it,:, n,
1, I, M, 5,,, a, n, forming the mnemonic expression n:?l ntma In,
Ethan, Moses, and Caleb] which are added in the derivation and infleuon
of words. We however employ the term root in a different sense, as explained here in No. 2.
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