pantomime horse 
noun British
A comic character in the form of a horse, played by two actors in one costume, one providing the front legs and operating the head, the other providing the back legs.If the plot allows, pantomime-writers also like to include an animal, cute like Jack Whittington's cat, or grotesque and funny inventions such as ‘Daisy the Cow,’ or a pantomime horse, visibly played by two humans....
- Some 150 people, many in costume, yesterday recreated a pagan sacrificial ritual - but using a pantomime horse, ‘sacrificed’ to bring good luck in the forthcoming year.
- A pantomime horse will be gracing the winners' enclosure at York Races on Saunday to drum up support for Marie Curie Cancer Care.