From Longman Dictionary of Contemporary Englishgumbootgum‧boot /ˈɡʌmbuːt/ noun [countable] British English old-fashioned DCCa tall boot made of rubber that you wear to keep your feet dry SYN wellington boot
Examples from the Corpus
gumboot• He turned up shortly after ten in gumboots, corduroys, pullover and the trusty green weatherproof.• Gates claims that its gumboots - made from natural rubber - are an altogether greener welly.• The right footwear for venturing the riverside path, short of gumboots.• It's already as big as Pa's gumboot.Origin gumboot (1800-1900) gum “rubber” + boot 