The word "cosh" is a noun that refers to a heavy, weighted object used as a weapon. It can also be used as a verb to mean hitting or striking someone with such an object. Full definition
They bludgeoned their victims over the head with coshes as they did in the Leeds robbery, relieving the store manager of # 4,000. (newlawjournal.co.uk)
Isometric stretching temporarily disables the stretch reflex but instead of the gentle persuasion that passive stretching uses, isometric stretching basically uses a giant cosh to hit the stretch reflex and give it no option but to relax whether it wants to or not. (unique-bodyweight-exercises.com)
Egoyan directs with a similar coshing touch, keen on the significant glance and the ariel shot of grieving parents, drenching the soundtrack in plinky reverb, giving the whole project the full TV movie treatment. (theguardian.com)