Wild (uncultivated) plants
By metaphor: plants that have grown in an abundant and uncultivated manner. Or: students who have strayed or departed on a mistaken path from what they learned. An extreme school of thought that emerged from any ideology.
("All the days of his vow of a Nazirite, no razor shall pass over his head... he shall let the locks of hair of his head grow long." - Numbers 6:5, Laws of the Nazirite)
Translation
Expression (Hebrew)
גִּדּוּלֵי פֶּרֶא
Definition (Hebrew)
בְּהַשְׁאָלָה: צְמָחִים שֶׁגָּדְלוּ בְּצוּרָה מְרֻבָּה וְלֹא מְטֻפַּחַת. אוֹ: תַּלְמִידִים שֶׁסָּרְחוּ אוֹ שֶׁפֵּרְשׁוּ בְּאֹרַח מֻטְעֶה אֶת מָה שֶׁלָּמְדוּ. אַסְכּוֹלָה קִיצוֹנִית שֶׁיָּצְאָה מֵאִידֵאוֹלוֹגְיָה כָּלְשֶׁהִי.
("כָּל יְמֵי נֶדֶר נִזְרוֹ תַּעַר לֹא יַעֲבֹר עַל רֹאשׁוֹ...גַּדֵּל פֶּרַע שְׂעַר רֹאשׁוֹ"- בַּמִּדְבָּר ו ה, הִלְכוֹת נָזִיר)