H2179. zinneb
[זִנֵּב] verbdenominative Pi`el cut off, or smite, the tail, only figurative, of hostile attack in war; Perfect consecutive 2 masculine plural וְזִנַּבְתֶּם [Josh 10:19] (followed by אֹתָם); Imperfect3masculine singular כָּלהַֿנֶּחֱשָׁלִים בְּךָ וַיְזַנֵּב [Deut 25:18]; in both = attack or smite in the rear.