squeeze box , n :
(caving) A box with an adjustable opening used by cavers to practise crawling through tight spaces. (veterinary medicine) A container that fits tightly around an animal to immobilize it for medical treatment, transportation, etc. […]
Source http://handbookblogger.blogspot.com/2017/10/squeeze-box-word-of-day-for-october-7.html
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