Noun
HESH
(military) Initialism of high explosive squash head.; a munition which uses a plastic explosive warhead that squashes on impact before exploding, causing spalling on the interior of armor panels when exploding.
Coordinate terms: HE, HEAT
However, base fuzes have been used with armour piercing shells and for squash head (HESH or HEP) anti-tank shells. Source: Internet
Main battle tanks usually use KE-penetrators, while HEAT is mainly found in missile systems that are shoulder-launched or vehicle-mounted, and HESH is usually favored for fortification demolition. Source: Internet
There are two types of these shells in use: high-explosive anti-tank (HEAT) and high-explosive squash head (HESH). Source: Internet