Rashi would sometimes derive the meaning of a word from the meaning
of its underlying Biblical root. In applying this method Rashi would use all
available grammatical methods to study the
meanings of related roots. The next paragraph presents one such rule.
There are 1900 Biblical roots. Of these 1900 roots about half involve X-Vav-Y X-Y-Y X-Y-Hey pairs. These roots (with one root letter weak) often, but not always, have related meanings. Consequently, very often, but not
always. one can infer the meaning of a X-Y-Y root from the related X-Y-Hey or
Rashi believed in two grammatical systems. He believed in the traditional tri-literial (3-letter) root methdos used to conjugate verbs and taught in all elementary schools.
Besides the conjugational root system Rashi also believed in a semantic root system. This is a separate system that enables derivation of root meaning from other roots.
For example the meaning of a 4-letter root, ABCD, is derived from the meaning of its two 2-letter subroots,
Rashi derives the meaning of the 3-letter root, Tauv-Nun-Caph, Tenuch as follows:
- Tauv-Vav-Caph, Toch means middle;
- Nun refers to characteristic/strong attribute;
- Hence Tauv-Nun-Caph, Tenuch means strongly middle and refers not
just to the two dimensional center of the air but refers to the part of the outer air with the hole of the ear canal
which brings sound through the ear canal. The technical name
for this is the external auditory meatus.
Some further examples where Nun refers to characteristic/strong
- Resh-Yud-Beth, Riv means to dispute; Resh-Yud-Beth-Nun, Yerivun, means to fight.
- Zayin-Yud-Kuph, Zik, means spark; Nun-Zayin-Kuph, Nezek, means
damage, a strong characteristic of sparks.
- Teth-Pay, Tippah, means Droplet;
Nun-Teth-Pay, NaTaph, refers to certain tree drippings, strongly characteristic of droplets.
- Ayin-Mem, Im means with; Nun-Ayin-Mem, Naim means pleasant,
strongly characteristic of withness.
- Tzade-Lamed, Tzayl means shade;
Nun-Tzade-Lamed, NaTzayl means salvation strong characteristic of
providing shade and removing one from "the heat."